MPs deserve a "one-off uplift" in their salaries, the head of the watchdog responsible for their pay and perks has insisted ahead of the publication of plans expected to set out an 11% rise.
Independent Parliamentary Standards Authority (Ipsa) chairman Sir Ian Kennedy said the issue should not be kicked into the long grass and despite the rise to help MPs' pay "catch up", the overall package will not cost taxpayers "a penny more".
Prime Minister David Cameron yesterday issued a veiled threat to abolish Ipsa if it presses ahead with the planned rise after the 2015 general election, insisting it was "simply unacceptable" that Members' salaries would increase by £7,600 to £74,000.
Opposition leader Ed Miliband has called on Mr Cameron and Nick Clegg to accompany him to an urgent meeting with Ipsa to demand an eleventh-hour halt to the wage hike.
But writing in The Times, Sir Ian insisted he would not be deterred by pressure from politicians.
He said: "I can see why some would want to wish the issue away, hoping we will do nothing or that a 'cross-party' review will provide the cover for kicking it into the long grass, just as happened with party funding years ago.
"That remains a position hard to argue with. We all know that MPs made a mess of these things for decades; the result was a disaster.
"We were given the job of tackling this issue independently for a reason. You are not independent if all you do is bend to the will of the Government or the Commons."
Sir Ian said the plan will involve a one-off rise, with MPs' wages then increasing at a more measured pace in line with other workers, in a plan designed to fix the issue for a generation.
Ipsa is planning a tougher-than-expected squeeze on MPs' pensions in a bid to cancel out the £4.6 million cost to the public purse. A £2.5 million saving by downgrading the final-salary scheme to career average - matching the rest of the public sector - had already been proposed alongside a crackdown on various perks.
Sir Ian said: "Reform is long overdue. Some of the benefits are unjustifiable. The pensions are too generous, the old resettlement payments too handsome and some of the expenses need further tightening.
"But the pay. The interest so often comes back to pay. We are in no doubt - MPs' pay needs a one-off uplift. Whatever measure you choose - including international comparisons and historic trends - they all lead to the same conclusion: MPs' pay has fallen behind. It needs to catch up.
"We will announce a one-off pay rise. Thereafter MPs' pay will move with the pay of the rest of us.
That's a sensible way forward, which we will implement after a further review of conditions in 2015.
"Despite some of the suggestions to the counter, this is also a good deal for taxpayers, as the overall package of reforms will not cost them a penny more."
MPs are acutely aware of the potential damage such a pay rise would cause with the public at a time when many workers are facing redundancy or pay cuts and freezes.
Mr Cameron suggested yesterday that abolition of Ipsa is on the table if it pushes ahead with the plans.
"First, the idea of an 11% pay rise in one year at a time of pay restraint is simply unacceptable," he told MPs.
"Secondly, Ipsa do need to think again and, unless they do so, I don't think anyone will want to rule anything out. No-one wants to go back to MPs voting on their own pay but we have got to have a process and an outcome that can build public confidence.
"Third, in my view, I think this should all be accompanied with a cut in the cost of politics."
The recommended pay rise will be subject to a statutory review by Ipsa after the 2015 contest, and Downing Street said the process should be allowed to run its course.
Mr Miliband wants the three main Westminster party leaders to meet Sir Ian immediately "to make clear our view that we cannot go ahead with the current proposition".
In a letter to Mr Cameron, the Labour leader said: "The public expect us to resolve this now and not wait until 2015. It only undermines confidence and trust in our political system if the uncertainty about MPs' pay is allowed to continue."