Nick Clegg has said he would not accept a pay rise if MPs were awarded one by the independent body that sets the rate as the public would not understand why he needed it.
The deputy prime minister's comments came amid reports that the Independent Parliamentary Standards Authority (Ipsa) is considering setting a pay rise of around £7,500, taking an MP's salary to £75,000.
Speaking at the first of his planned Whitehall news conferences, Clegg made clear that a rise on such a scale would be unacceptable to voters.
"My own view is that the public would find it impossible to understand - particularly as (there are) millions of people in the public sector whose pay is only increasing by 1% - that their parliamentary representatives at a time like this would be receiving pay increases far in excess of that 1% increase," he said.
"Speaking for myself I would certainly seek to do whatever I can to make sure that either this decision is not taken in the first place - but that's out of my hands - but, secondly, if were to be taken, not to take that pay increase."
David Cameron has already urged Ipsa to "show restraint" warning it would be "unthinkable" to make Westminster more expensive to the taxpayer, while Labour leader Ed Miliband has also signalled his opposition to such a large increase.
According to weekend newspaper reports, sources have indicated the regulator would suggest raising MPs' pay to £75,000 a year, in a series of upratings starting in 2015, coupled with much higher pension contributions.
Cameron said he did not know what the independent body would recommend. But he added: "Whatever Ipsa recommends we can't see the cost of politics or Westminster going up. We should see the cost of Westminster go down."
He added: "Anything would be unthinkable unless the cost of politics was frozen and cut, so I'll wait and see what Ipsa have to say. What I said to Ipsa was that restraint is necessary."
However not all MPs think the current wage was enough. Tory Mark Pritchard said that the low level of pay was driving good people away from politics.
"I think there should be a pay rise, but I don't think the time is right now," he said. "The majority of people who came into parliament took a major pay cut."
Pritchard told Sky News "most sensible people" would recognise MPs pay was too low when compared to politicians from other European countries.
And he said MPs could not win in the eyes of the media as they were attacked if they earned money from other jobs but were also attacked if they shunned outside work but asked for a pay increase. "Everything we do we are criticised," he said.