Downing Street has declined to say whether David Cameron will accept an 11% pay rise expected to be recommended by MPs' independent standards watchdog.
Senior politicians have condemned the plan being drawn up by the Independent Parliamentary Standards Authority (Ipsa) for a £7,600 hike in MPs' salaries to £74,000 after the 2015 general election.
Defence Secretary Philip Hammond indicated that he would not accept the extra cash while armed forces pay was being pegged back - and suggested Cabinet ministers would agree a united approach.
Liberal Democrat Chief Secretary to the Treasury Danny Alexander said the public would find it "utterly incomprehensible" if Ipsa defied concerted calls from Mr Cameron, Ed Miliband and Nick Clegg to show restraint.
Asked whether the Prime Minister would accept the rise, Mr Cameron's official spokesman told a regular Westminster media briefing: "I don't believe Ipsa have made a formal proposal yet. Any proposal that they make will be reviewed in mid-2015.
"The Prime Minister's long-standing position is that the cost of politics should go down, not up. He doesn't think that MPs' pay should go up while public sector pay is being restrained."
Ipsa was given responsibility for Westminster pay and perks in the wake of the expenses scandal. MPs were stripped of the power to set their own pay in a move intended to take the issue out of the arena of political controversy.
In an anonymous survey conducted by Ipsa earlier this year, MPs suggested that they should be paid an average of £86,250, with one-fifth of those questioned saying they should get £95,000 or more.
Asked if the Prime Minister continued to have confidence in Ipsa, the spokesman said: "He thinks that it was right for Parliament to come together and make the decisions that it took with regards to making pay independent."
Charles Walker, Conservative MP for Broxbourne, said he "absolutely" would take the pay rise planned by Ipsa.
He told BBC Radio 4's World at One programme: "I've been working since I left university for 25 years and I have never turned a pay rise down and I don't intend to start turning any future pay rises down.
"Look, I am the Member of Parliament for Broxbourne. They have neither elected a saint or a millionaire. I am a flawed human being, with many flaws, but, I'm afraid, I will accept the pay rise."
Mr Walker took a swipe at Nick Clegg whose wife Miriam is a high-earning lawyer, telling the programme: "There's not many people who would turn down a pay rise except those, perhaps, who view being a Member of Parliament, or dare I say, the Deputy Prime Minister as somewhat of a hobby job which is supported by a high earning spouse."