Question: What political party stopped the construction of the Thames Gateway Bridge

full_context: Document 1: Jeremy Hunt: Jeremy Richard Streynsham Hunt {'1': ", '2': ", '3': ", '4': "} (born 1 November 1966) is a British Conservative Party politician who has been the Secretary of State for Health since 2012 and the Member of Parliament for South West Surrey since 2005. He was previously Culture Secretary (2010–12).
Document 2: King's Cross Thameslink railway station: King's Cross Thameslink station is a closed railway station in central London, England. It served the Thameslink route but was replaced by new Thameslink platforms at St Pancras in December 2007. The last operator of the station was First Capital Connect. The site is on Pentonville Road, about 160 yd from King's Cross station.
Document 3: Boris Johnson: Alexander Boris de Pfeffel Johnson (born 19 June 1964), known as Boris Johnson, is a British politician, popular historian and journalist. He has served as Secretary of State for Foreign and Commonwealth Affairs since 2016 and as Member of Parliament (MP) for Uxbridge and South Ruislip since 2015. He had previously been MP for Henley from 2001 to 2008 and Mayor of London from 2008 to 2016. A member of the Conservative Party, Johnson identifies as a one-nation conservative and has been associated with both economically and socially liberal policies.
Document 4: Michael Gove: Michael Andrew Gove ( ; born 26 August 1967) is a British Conservative politician, who was Secretary of State for Education from 2010 to 2014 and Secretary of State for Justice from 2015 to 2016. He became Secretary of State for Environment, Food and Rural Affairs in the cabinet reshuffle on 11 June 2017. He has been the Member of Parliament (MP) for Surrey Heath since 2005. He is also an author and a columnist for "The Times".
Document 5: Thames Gateway Bridge: The Thames Gateway Bridge was a proposed crossing over the River Thames in east London, England. It was first mooted in the 1970s but never came to fruition. In November 2008, Boris Johnson, the then Mayor of London, formally cancelled the entire £500 million scheme.
Document 6: George Osborne: George Gideon Oliver Osborne, (born Gideon Oliver Osborne; 23 May 1971) is a British Conservative Party politician, who was Member of Parliament (MP) for Tatton from June 2001 until he stood down on 3 May 2017. He served as Chancellor of the Exchequer under Prime Minister David Cameron from 2010 to 2016. He has been editor of the "London Evening Standard" since May 2017.
Document 7: Downings Roads Moorings: Downings Roads Moorings is a mooring for barges on the River Thames near Tower Bridge that is home to a small community of houseboat dwellers in Central London. In 2003 and 2004, they were threatened with eviction by Southwark Council. The members of the community appealed. The then Mayor of London Ken Livingstone commented in a letter to Southwark Council that "The principle of retaining the moorings is supported by the London Plan policy 4C.19 and supporting text contained in paragraphs 4.117 and 4.118. The mix of uses proposed for these moorings should be seen as broadly acceptable in the context of a multi functional Blue Ribbon Network as long as there are appropriate amenity and environmental safeguards in place.". Their eviction was quashed in late 2004.
Document 8: Tower Bridge: Tower Bridge is a combined bascule and suspension bridge in London built between 1886 and 1894. The bridge crosses the River Thames close to the Tower of London and has become an iconic symbol of London, resulting in it sometimes being confused with London Bridge, situated some 0.5 mi upstream. Tower Bridge is one of five London bridges now owned and maintained by the Bridge House Estates, a charitable trust overseen by the City of London Corporation. It is the only one of the Trust's bridges not to connect the City of London directly to the Southwark bank, as its northern landfall is in Tower Hamlets.
Document 9: John Major: Sir John Major, {'1': ", '2': ", '3': ", '4': "} (born 29 March 1943) is a British politician who was Prime Minister of the United Kingdom and Leader of the Conservative Party from 1990 to 1997. He served as Foreign Secretary and then Chancellor of the Exchequer in the Thatcher Government from 1989 to 1990, and was the Member of Parliament (MP) for Huntingdon from 1979 until he retired in 2001. Since Margaret Thatcher's death in 2013, he is the oldest living former Prime Minister.
Document 10: David Cameron: David William Donald Cameron ( ; born 9 October 1966) is a British politician who was Prime Minister of the United Kingdom from 2010 to 2016 and Leader of the Conservative Party from 2005 to 2016. He was Member of Parliament (MP) for Witney from 2001 to 2016. Cameron identifies as a One-Nation Conservative, and has been associated with both economically liberal and socially liberal policies.
Document 11: Proposed Thames Airport: Thames Airport was a proposed elevated airport during the 1930s that would have been constructed over the River Thames between Westminster Bridge and Lambeth Bridge. Not much is known about the proposed airport, except that it would have had an elevator to bring people to the flight deck, as well as room underneath for a hangar. It would have also been next to the nearby Big Ben and Palace of Westminster.
Document 12: London Docklands: London Docklands is the name for the riverfront and former docks in London, capital of the United Kingdom, based around east and south east London respectively. It forms part of the boroughs of Southwark, Tower Hamlets, Lewisham, Newham and Greenwich. The docks were formerly part of the Port of London, at one time the world's largest port. They have now been redeveloped principally for commercial and residential use. The name London Docklands was used for the first time in a government report on redevelopment plans in 1971 and has since become virtually universally adopted. It also created conflict between the new and old communities of the London Docklands.
Document 13: Chris Skidmore: Christopher James Skidmore, {'1': ", '2': ", '3': ", '4': "} (born 17 May 1981) is a British politician, author, and historian. He has served since 2010 as the Conservative Member of Parliament (MP) for Kingswood, South Gloucestershire, and in 2015 became Parliamentary Private Secretary to the Chancellor of the Exchequer. When Theresa May became Prime Minister in 2016 he was appointed Parliamentary Secretary at the Cabinet Office, where he is described as Minister for the Constitution.
Document 14: Upper Thames River Conservation Authority: The Upper Thames River Conservation Authority is a body based in London, Ontario, Canada. It was created in 1947. It was responsible for the construction of the Fanshawe Dam, completed in the 1950s, to control flooding from the Thames River, which runs through London. During the last ice age, the site of London was the terminus of a large glacier. When the region warmed at the end of the ice age, the glacier melted and receded North, leaving behind a drainage ditch and features such as Sifton Bog. As such, the Thames is a watershed for most of Western Ontario, and is therefore highly susceptible to seasonal flooding. In 1937, such flooding had devastating consequences, destroying over 1,000 homes, and causing millions of dollars in damage.
Document 15: More London: More London, also named London Bridge City, is a privately owned development on the south bank of the River Thames, immediately south-west of Tower Bridge in London. The southern exit is on Tooley Street.
ground_truth: the Conservative Party