Chancellor Philip Hammond is preparing a "revolutionary" budget to get the Government back on track after weeks of speculation about his political future, according to reports.
Cabinet ministers have been asked to come up with "bold" proposals after intentions for a "safety first" financial statement were dropped following weeks of Tory turmoil.
Mr Hammond is under intense pressure after angering Brexiteers in the party by refusing to prepare for the possible failure of Britain and Brussels to reach an agreement over a Brexit deal.
Concerns the Chancellor is "trying to frustrate the negotiating process" have also been reportedly raised by the DUP, which props up the minority Tory government.
Mr Hammond is said to be looking at measures to boost housing, including urging Prime Minister Theresa May to agree to allow building on green belt as well as letting councils borrow more to help create new homes.
He is also considering writing off student loans and dropping opposition to borrowing to boost investment, according to The Sunday Times.
A Government source told the newspaper: "Philip has said that we have to have a radical budget, something that is a big offer to the nation."
The DUP, meanwhile, is said to be "very concerned" about Mr Hammond's behaviour.
A party source told The Sunday Telegraph: "It is evident to us that he is winding people up and causing unnecessary division within the Conservative Party at a crucial time in the Brexit negotiations, and his behaviour is very unsettling.
"One has to wonder what his motivation is. He appears to be at least highly sceptical about Brexit and one could conclude from his current position and his behaviour that he is trying to frustrate the negotiating process and to undermine the Prime Minister.
"The DUP will continue to keep a close watch on the situation but we think that Mrs May needs to do something to rein her Chancellor in and to make it clear to him that this kind of behaviour has to stop.
"It is not for us to dictate to the Prime Minister how she should manage her Cabinet but as informed observers with a vested interest in making Brexit work we are deeply concerned. If this behaviour continues the Chancellor's position becomes untenable."