London Mayor Boris Johnson today warned that middle income families were feeling "utterly and understandably ignored", as he prepared to address the Conservative conference in Birmingham.
Mr Johnson's arrival in Birmingham threatens to overshadow events in the conference chamber, after polls suggesting that he outstrips Prime Minister David Cameron in public popularity thanks to his re-election as Mayor and his much-applauded handling of the summer's Olympic Games.
Today, he once again used a press article to highlight apparent differences with the Government, following earlier clashes over Europe, the proposed third runway at Heathrow and funding for infrastructure projects in the capital.
Writing in the Daily Telegraph, Mr Johnson called for more help for the "struggling middle" - working families with incomes ranging from £30,000 to £64,000 - particularly regarding issues like housing.
"They are not being helped," he wrote. "They are feeling utterly and understandably ignored. It is time to help them."
Mr Johnson yesterday sought to play down speculation that he is positioning himself to succeed Mr Cameron as Conservative leader and Prime Minister, insisting that it was a "distraction" from his job as London Mayor.
But in an interview for Pienaar's Politics on BBC Radio 5 Live on the opening day of conference, it was notable that he avoided ruling out a future bid for the party's top job.
Asked if he believed Mr Cameron was doing a better job as PM than he could, he would only say that the question was "unverifiable".
And challenged over whether he harboured ambitions to be PM, he said that what he wanted to be was Mayor "certainly for the next few years", adding: "After four years are up, heaven knows. I will be an old man."
Mr Cameron was the best man to run the country "now", he said, adding that it was "perfectly natural" for the media to construct a narrative in which the two men were in competition, as his position as a representative of London's interests "inevitably" brought him into conflict with the Government.
"My function is to run London, I have been elected to do that, and David Cameron is overwhelmingly the best man now to lead this country, to clear up the mess that Labour left, and I think he is doing a bang-on job," said Mr Johnson.
Mr Cameron - who hosted Mr Johnson for pre-conference weekend drinks at a pub near Chequers - sought to play down any suggestion of rivalry with the London Mayor.
"I have got the opposite of tall poppy syndrome," the PM told BBC1's Andrew Marr Show. "I like having other people in the Conservative Party who are popular, who get out there, talk our message and explain our vision and values.
"I have said to Boris: 'Once you have done your job as London mayor, don't think your job in politics is over.' I think he has got a huge amount to offer, a huge amount to give and I encourage him to do that."
But there is little doubt that Mr Johnson's presence in Birmingham will divert attention from Mr Cameron and his Cabinet colleagues, including Chancellor George Osborne, who is giving his keynote speech today.
The Mayor will address a rally staged by the influential Conservative Home website under the triumphal banner "Re-elected and Olympotastic".
Tomorrow, he will address the conference itself, buoyed by the survey by pollsters Opinium for The Observer which gave him a net +30 rating, compared to -21 for the Prime Minister.