Boris Johnson made a new pitch to Tory right-wingers today, as he called for tough restrictions on public sector strikes and a big tax cut for Britain's highest-earners.
The London mayor called on the chancellor to cut the top rate of tax from 45p to 40p.
"The government should open up some more blue water, and cut the top rate back to 40p," he wrote in the Telegraph, accusing Labour of "idiocy" for wanting the top rate of tax to return to 50p.
He has previously called for the top rate of tax to go down as low as 30p.
He also mocked the shadow chancellor Ed Balls for having "the pop-eyed air of a man undergoing an unexpected prostate examination".
Speaking at a mayoral event this morning, Johnson called on the government to ban any public sector strike where less than 50% of the workforce have taken part in the vote.
"This is something I wanted the coalition to do from the very beginning. We haven't been able to do that and I'm reconciled to that now," he told the Times.
"Maybe it will be in our manifesto. I think it would be good if Dave put it in. I think there's a good chance he will."
Sources close to the mayor claimed they were "fairly certain" the policy would be adopted by the party.
Labour today accused Johnson of only standing up for the wealthiest Londoners.
"Today Boris has confirmed he is the Mayor for the one per cent," Labour London Assembly member Fiona Twycross said.
"When times are tough it is only right and fair that those with the broadest shoulders bare the greatest burden. Since Boris was re-elected in May 2012 he has met with senior bankers at least ten times.
"Yet he cannot find the time to visit a food bank and see first-hand how ordinary people are struggling to earn enough to feed themselves and their families."
Johnson's interventions come as fears grow in Tory circles that the party leadership has not translated the economic recovery into a boost for the party in the polls.
The prime minister is expected to face a rebellion from his backbenchers later this week as they grow restless for him to take a harder line on Europe and immigration.
A recent survey of Tory activists found that Johnson is now joint favourite to replace Cameron, alongside the Home Secretary Theresa May.
Johnson's appearance at an event to mark the "year of the bus" was almost brought to a halt today by three anti-homelessness protesters.
In chaotic scenes, the mayor was heard to shout "Tally ho" as the three protesters sounded their horns