Five of the most damning political U-turns
Phillip Hammond isn't the only one to be left red-faced. Here are some other politicians left backtracking on a pledge
Philip Johnston in the Daily Telegraph even called it a "political humiliation for the history books".
However, he's not the only politician to have backtracked on policies and promises. Here we take a look at five of the most damning U-turns in modern British politics.
Top spot in our list has to go to Ted Heath, who, according to the Guardian’s Tim Bale, was the "undisputed king of the u-turn".
He didn't just go back on a solo scheme; he went back on an entire manifesto.
In 1970, the Tories' general election promises focused on cutting back public expenditure. Once in power, however, as unemployment rose to more than one million for the first time since 1947 and the country was hit by strike after strike, Heath had to back down, pouring money into the NHS, education and welfare.
Ultimately, this cost him the political premiership – and the leadership of the party, paving the way for Margaret Thatcher to take over.
Who would have thought the humble pasty could challenge a prominent politician?
Former chancellor George Osborne is infamous for his U-turn on the pastry's tax credentials after his decision in 2012 to impose VAT on hot baked goods prompted a public outcry.
Bakery chain Greggs threatened job cuts, the Cornish community protested and commentators decried it as an austerity step too far.
The consequence was a humiliating reversal of Osborne’s policy, an episode that will forever be known as "Pastygate".
Once in office in the coalition, deputy prime minister Nick Clegg reversed his manifesto pledge as leader of "student party" the Liberal Democrats and voted in favour of increasing tuition fees to £9,000 per academic year.
Despite later apologising for the U-turn, which caused furore at the time, Clegg's ratings never recovered and the issue was seen by many as the reason the Lib Dems suffered such heavy losses in the 2015 general election.
The legal classification of cannabis has led to many scratched heads over the years.
In 2004, David Blunkett, home secretary in Tony Blair's government, downgraded the drug from class B to class C, removing the threat of arrest for possession.
However, Blair's successor as prime minister, Gordon Brown, reclassified it as a class B drug in 2009.
Even though Blunkett's action was sanctioned by the Advisory Council on the Misuse of Drugs, the U-turn was seen as a "damning admission that Labour's soft policy… was a mistake".
Scrapping the 10p tax rate
As chancellor in 2007, Brown announced he was getting rid of the 10p starting rate of income tax, which had existed since 1999.
The change meant all income above the personal allowance would be subject to the "basic rate" of income tax at 20 per cent.
The move led to a rebellion in the Labour ranks and widespread criticism from the public.
As a result, Alistair Darling was forced to borrow almost £3bn to compensate those affected when he took over at the Exchequer.