Deputy Prime minister and Leader of the Liberal Democrats, Nick Clegg, talks to the FT on a train to his constituency in Sheffield.

Charlie Bibby/FT

Deputy Prime minister and Leader of the Liberal Democrats, Nick Clegg is photographed during an interview on a train. Clegg was on his way to his constituency in Sheffield 

People walk in front a poster of prominent attendees of the 1955 Asian-African Conference on Asia Afrika street in Bandung...People walk in front a poster of prominent attendees of the 1955 Asian-African Conference on Asia Afrika street in Bandung, Indonesia, April 24, 2015. Leaders of Asian and African nations attended a commemoration ceremony on Friday marking 60 years since the commemoration of the Asian-African Conference.  REUTERS/Beawiharta

Beawiharta/Reuters

People walk in front a poster of prominent attendees of the 1955 Asian-African Conference on Asia Afrika street in Bandung, Indonesia

An elderly woman sits on ground as she is blocked by barricade of policemen while marching down street during rally in central Seoul...An elderly woman sits on the ground as she is blocked by a barricade of policemen while marching down the street during a rally in central Seoul, South Korea, April 24, 2015. About 260,000 workers took part in the nationwide one-day strike, including about 60,000 government employees and 10,000 teachers, according to the Korean Federation of Trade Unions. They protested against the government's push to cut pensions and ease rules for firing employees, according to local media.  REUTERS/Kim Hong-Ji

Kim Hong-Ji/Reuters

An elderly woman sits on the ground as she is blocked by a barricade of policemen while marching down the street during a rally in central Seoul, South Korea. About 260,000 workers took part in the nationwide one-day strike, including about 60,000 government employees and 10,000 teachers, according to the Korean Federation of Trade Unions. They protested against the government’s push to cut pensions and ease rules for firing employees, according to local media 

ATTENTION EDITORS - CAPTION CORRECTION FOR LON101 TRANSMITTED ON APRIL 23, 2015 AT APPROXIMATELY 0830 GMT...ATTENTION EDITORS - CAPTION CORRECTION FOR LON101 TRANSMITTED ON APRIL 23, 2015 AT APPROXIMATELY 0830 GMT. THE CAPTION INCORRECTLY MENTIONS A PUSH CHAIR. A CORRECTED VERSION IMMEDIATELY FOLLOWS THIS ADVISORY. WE ARE SORRY FOR ANY INCONVENIENCE CAUSED. REUTERS.  A woman walks past a piece of street art depicting a pregnant Catherine, Duchess of Cambridge, in north London, April 23, 2015. The Duchess is due to give birth to her second child in the next few days.  REUTERS/Cathal McNaughton TPX IMAGES OF THE DAY  TEMPLATE OUT

Cathal McNaughton/Reuters

A woman walks past a piece of street art depicting a pregnant Catherine, Duchess of Cambridge, in north London. The Duchess is due to give birth to her second child in the next few days. 

Women wearing sevillana dresses are seen during the traditional Feria de Abril (April fair) in the Andalusian capital of Seville...ATTENTION EDITORS: SPANISH LAW REQUIRES THAT THE FACES OF MINORS ARE MASKED IN PUBLICATIONS WITHIN SPAIN Women wearing sevillana dresses are seen during the traditional Feria de Abril (April fair) in the Andalusian capital of Seville, southern Spain, April 23, 2015. The fair will run until April 26.  REUTERS/Marcelo del Pozo        TPX IMAGES OF THE DAY

Marcelo del Pozo/Reuters

Women wearing sevillana dresses are seen during the traditional Feria de Abril (April Fair) in the Andalusian capital of Seville, southern Spain

Ring-tailed lemurs are pictured at Zoom ...Ring-tailed lemurs are pictured at Zoom Torino, a zoological park in Cumiana near Turin, on April 22, 2015. Zoom Torino is a new immersive zoological park, where animals can be seen without bars or cages, only natural barriers ensure the visit. AFP PHOTO / MARCO BERTORELLOMARCO BERTORELLO/AFP/Getty Images

Marco Bertorello/AFP/Getty

Ring-tailed lemurs are pictured at Zoom Torino, a zoological park in Cumiana near Turin, Zoom Torino is a new immersive zoological park, where animals can be seen without bars or cages, only natural barriers ensure the visit

An aerial shot shows the skylines of Hon...An aerial shot shows the skylines of Hong Kong island (foreground) and Kowloon (back L) separated by Victoria harbour on April 23, 2015, a day after the city's government unveiled its Beijing-backed plan for leadership elections in 2017. Britain handed Hong Kong over to China in 1997 under a joint declaration which guaranteed political, social and economic freedoms not enjoyed on the Chinese mainland.  AFP PHOTO / Philippe LopezPHILIPPE LOPEZ/AFP/Getty Images

Philippe Lopez/AFP/Getty

An aerial shot shows the skylines of Hong Kong island (foreground) and Kowloon (back left) separated by Victoria harbour. The city’s government on Wednesday unveiled its Beijing-backed plan for leadership elections in 2017.

Steam Train Provides Link Between China's Past And Present...SHIXI, CHINA - MARCH 27: Workers service  a local coal powered steam train before departing on a trip carrying local villagers on March 27, 2015 at a station in the town of Shixi , Sichuan Province, in Southern China. While China boasts the world's most extensive high-speed rail infrastructure with over 16,000 kilometers of track, the Shixi-Bagou railway is still a primary connection for local villagers between towns and is kept alive by tourist cars carrying passengers for ten times the price. The rail line came into service in the late 1950s and the train was initially used to transport coal from a now-shuttered mine before passenger carriages were added.  (Photo by Kevin Frayer/Getty Images)

Kevin Frayer/Getty

China boasts the world’s most extensive high speed rail network with more than 16,000 km of track, but steam trains still have a role to play. The Shixi-Bagou railway connects the two towns and is kept going by tourist cars carrying passengers for ten times the price locals pay. The rail line came into service in the late 1950s and the train was initially used to transport coal from a now-shuttered mine before passenger carriages were added. 

Wider Image: Renting in Mumbai Per Square Foot...Residents look out of windows of an apartment in Mumbai March 15, 2015. The cost for buying a 200 square feet (18 square meters) one-bedroom apartment in this building is around 25,000 Indian rupees per square feet ($ 400) or 5,000,000 Indian rupees ($ 80,000). The rent for an apartment in the same building is around 12,000 Indian rupees ($ 190) per month. REUTERS/Danish Siddiqui  TPX IMAGES OF THE DAY PICTURE 05 OF 22 FOR WIDER IMAGE STORY "RENTING IN MUMBAI PER SQUARE FOOT" SEARCH "RENTING SIDDIQUI" FOR ALL IMAGES

Danish Siddiqui/Reuters

Residents look out of windows of an apartment in Mumbai, India. The cost of buying a 200 sq ft one-bedroom apartment in this building is around Rs5m ($80,000). The rent for an apartment in the same building is around Rs12,000 ($190) per month 

The shadow of Britain's Prime Minister Cameron is cast on a screen as he delivers a speech in a garden shed warehouse during a campaign event in Bedford, southern...The shadow of Britain's Prime Minister David Cameron is cast on a screen as he delivers a speech in a garden shed warehouse during a campaign event in Bedford, southern England April 22, 2015.  REUTERS/Toby Melville

Toby Melville/Reuters

The shadow of Britain’s Prime Minister David Cameron is cast on a screen as he delivers a speech in a garden shed warehouse during a campaign event in Bedford, southern England 

Protesters Hold Vigil And March Over Death Of Freddie Gray After Police Arrest...BALTIMORE, MD - ARPIL 21:  Protestors walk toward Baltimore Police Department's Western District police station during a march and vigil over the death of Freddie Gray, April 21, 2015 in Baltimore, Maryland.  Gray, 25, died from spinal injuries on April 19, one week after being taken into police custody. (Photo by Drew Angerer/Getty Images)

Drew Angerer/Getty

Protestors walk towards Baltimore Police Department’s Western District police station during a march and vigil over the death of Freddie Gray in Baltimore, Maryland 

Local people and members of National Disaster Response Force clear the debris of a residential building to look for the survivors, in New Delhi, India, Wednesday, April 22, 2015.  One man and a child were killed and at least nine others were injured when a three-storey residential building collapsed following an explosion in a cooking gas cylinder, according to local news agency Press Trust of India. (AP Photo / Manish Swarup)

Manish Swarup/AP

Local people and members of National Disaster Response Force clear the debris of a residential building to look for the survivors, in New Delhi, India. One man and a child were killed and at least nine others were injured when a three-storey residential building collapsed following an explosion in a cooking gas cylinder, according to local news agency Press Trust of India

Boris Johnson today campaigned in Ramsgate, in the Thanet South constituency on behalf of Conservative candidate, Criag McKinlay.

Charlie Bibby/FT

Boris Johnson campaigns in Ramsgate, in the Thanet South constituency, on behalf of Conservative candidate, Craig McKinlay 

Nick Clegg Campaigns in Cornwall...NEWLYN, ENGLAND - APRIL 21:  Deputy Prime Minister Nick Clegg chats on board a fishing vessel with market manager Lionel Washer (L), Andrew George, MP for St Ives (2R) and Harbour Master Rob Parsons (R) at Newlyn Harbour on April 21, 2015 in Cornwall, England. The Liberal Democrat party leader visited the harbour to campaign alongside Liberal Democrat candidate and MP of 18 years Andrew George and meet members of the fishing community. Britain goes to the polls in a general election on May 7.  (Photo by Matt Cardy/Getty Images)

Matt Cardy/Getty

Deputy Prime Minister Nick Clegg chats on board a fishing vessel with market manager Lionel Washer (L), Andrew George, MP for St Ives (2R), and Harbour Master Rob Parsons (R) at Newlyn Harbour on Tuesday in Cornwall, England 

TOPSHOTS Lightning brightens the night s...TOPSHOTS Lightning brightens the night sky over Washington, DC, during a rainstorm on April 20, 2015.  AFP PHOTO / MLADEN ANTONOVMLADEN ANTONOV/AFP/Getty Images

Mladen Antonov/AFP/Getty

Lightning brightens the night sky over Washington D.C. during a rainstorm

Britain's Prime Minister Cameron delivers a speech with Chancellor of the Exchequer Osborne at Arriva TrainCare in Crewe in northern England...Britain's Prime Minister David Cameron (R) delivers a speech with Chancellor of the Exchequer George Osborne during a campaign stop at Arriva TrainCare in Crewe in northern England, April 20, 2015. REUTERS/Toby Melville

Toby Melville/Reuters

Britain’s Prime Minister David Cameron delivers a speech with Chancellor of the Exchequer George Osborne during a campaign stop at Arriva TrainCare in Crewe in northern England 

Workers clean windows of a building at a commercial district in Beijing...Workers clean windows of a building at a commercial district in Beijing April 20,  2015. China's central bank on Sunday cut the amount of cash that banks must hold as reserves, the second industry-wide cut in two months, adding more liquidity to the world's second-biggest economy to help spur bank lending and combat slowing growth. Weighed down by a property downturn, factory overcapacity and local debt, growth is expected to slow to a quarter-century low of around 7 percent this year from 7.4 percent in 2014, even with expected additional stimulus measures. REUTERS/Kim Kyung-Hoon       TPX IMAGES OF THE DAY

Kim Kyung-Hoon/Reuters

Workers clean windows of a building at a commercial district in Beijing 

Rescuers help children to disembark in the Sicilian harbor of Pozzallo, Italy, early Monday, April 20, 2015. About 100 migrants, including 28 children, were rescued on Sunday by a merchant vessel in the Sicilian Strait while they were trying to cross. Another smuggler's boat crammed with hundreds of people overturned off Libya's coast on Saturday as rescuers approached, causing what could be the Mediterranean's deadliest known migrant tragedy and intensifying pressure on the European Union Sunday to finally meet demands for decisive action. (AP Photo/Alessandra Tarantino)

Alessandra Tarantino/AP

Rescuers help children to disembark in the Sicilian harbor of Pozzallo, Italy, early on Monday. About 100 migrants, including 28 children, were rescued on Sunday by a merchant vessel in the Sicilian Strait while they were trying to cross. Another smuggler’s boat crammed with hundreds of people overturned off Libya’s coast on Saturday as rescuers approached, causing what could be the Mediterranean’s deadliest known migrant tragedy and intensifying pressure on the European Union Sunday to finally meet demands for decisive action 

Sotheby's Arts of the Islamic World auction. An Ottoman jewelled presentation sword. Turkey. 18th/19th century. Photograph: Rosie HallamSotheby's Arts of the Islamic World auction. Photograph: Rosie Hallam

Rosie Hallam/FT

A Sotheby’s member of staff presents a 18th/19th Century Ottoman jewelled presentation sword at a media preview of the Arts of the Islamic World at Sotheby’s, London 

Spring weather April 16th 2015...The aurora borealis, or the northern lights as they are commonly known, takes place over the Bathing House in Howick, Northumberland, in the early hours of this morning.

Owen Humphreys/PA

Aurora Borealis, commonly known as the Northern Lights, takes place over the Bathing House in Howick, Northumberland, in the early hours of Thursday morning