Downing Street has made a fresh appeal to the body that sets MPs’ pay to abandon plans for a £7,000 rise.
It said in a letter to the Independent Parliamentary Standards Authority that the planned rise was “not appropriate”.
Ipsa has said unless there is “new and compelling evidence,” MPs’ pay will rise by 10%, from £67,060 to £74,000.
BBC assistant political editor Norman Smith said PM David Cameron was under pressure after many opposition MPs said they would give the money to charity.
Labour’s leadership hopefuls Andy Burnham, Yvette Cooper and Liz Kendall have said they will reject the extra money and Labour leader Harriet Harman is thought likely to do so, our correspondent said.
Education Secretary Nicky Morgan, SNP leader Angus Robertson and Lib Dem leadership hopeful Tim Farron have all said they will give the money to charity.