Ed Miliband will move to put “fair and impartial leaders’ debates” on a statutory footing in an effort to avoid them becoming subject to the kind of political wrangling that has characterised the programmes scheduled for next month in the run-up to polling day.
The new system would work on similar lines to the current rules for planning the number, length and timing of party political broadcasts.
That would mean parties are consulted but not given the right to veto the debates taking place.
The four broadcasters - the BBC, ITV, Sky and Channel 4 - have said they will stick to their previously-announced plans for three debates during the election campaign, and urged the Prime Minister to “reconsider” his refusal to take part in these shows, including a head-to-head showdown with Mr Miliband.
But Mr Cameron’s chief spin doctor Craig Oliver said their response was “disappointing” and restated the Prime Minister’s “final position” was for a single debate to take place in the week starting March 23.
The broadcasters said they would stick to plans for a seven-way debate involving Mr Cameron, Mr Miliband, Nick Clegg of the Lib Dems and the leaders of the Greens, Ukip, Scottish National Party and Plaid Cymru on ITV on April 2, followed by a second show on BBC featuring the same line-up on April 16.
A final one-on-one clash with the Tory and Labour leaders invited is scheduled to be broadcast on Sky News and Channel 4 on April 30 - exactly a week before the May 7 election.
MPs will consider the debates row on Wednesday in response to a motion tabled by the Democratic Unionist Party , which is threatening to seek a judicial review over its exclusion from the TV showdowns.
The DUP’s Westminster leader Nigel Dodds said: “It’s difficult to think of a recent political event more badly managed by the people who wanted it most.”