David Cameron... has stated that he is
certainly a big Thatcher fan, but I don't know whether that makes me a Thatcherite,which means he's not. Since he is
not deeply ideologicalhe lacks core principles and is easily led. He has been described as
certainly not a Pitt, Elder or Younger,but he does wear a nice suit so maybe he's Beau Brummel ...
The comments from Mr Johnson, known for his messy shock of blond hair and clownish soundbites, end months of speculation about whether he would return to national politics.
Some in Mr Cameron's Conservative Party see Mr Johnson as a popular figure with a high profile who could be a successful future leader if he were to win a seat at May's general election.
"In all probability I will try to find somewhere to stand in 2015," Mr Johnson said following a speech in London.
But Mr Johnson, 50, also said he intended to serve out his full term as London's mayor, which does not end until 2016. He has always played down his chances of eventually becoming prime minister, saying they were about as good as those "of finding Elvis on Mars or my being reincarnated as an olive".
Mr Cameron's Conservatives, currently senior partners in a coalition government, face a tough fight to win next year's election. A YouGov/Sun poll out on Wednesday put the Conservatives on 33 per cent, the main opposition Labour on 38 per cent, junior coalition partners the Liberal Democrats on 8 per cent and the anti-EU UK Independence Party on 12 per cent.
Mr Johnson and Mr Cameron are old rivals who attended the elite Eton College and Oxford University together.