BBC INVITES MILIBAND AND CLEGG TO SIX-WAY “CHALLENGER” DEBATE — BUT CAMERON NOT ASKED TO ATTEND

The TV election debates were thrown into further chaos this evening after it emerged that Labour and the Liberal Democrats have been invited to join the four smaller parties in a six-way BBC “challenger” debate.

Proposals put forward by the broadcasters earlier this week, which were accepted by David Cameron, envisaged only one debate involving the leaders of the three main parties, who would take part in a seven-way ITV debate on April 2.

Mr Cameron has repeatedly refused to take part in a similar seven-way BBC event, and so the corporation had instead planned to hold a smaller contest, on April 16, featuring just the leaders of Ukip, the Greens, the SNP and Plaid Cymru.

But after protests from Labour, who are keen to portray Mr Cameron as weak for rejecting initial proposals that he should take part in three debates, the BBC has now agreed to broaden its challenger event, to include Labour and the Lib Dems.

It is understood that Mr Cameron will not be invited to take part in the BBC debate, to avoid the corporation having to deal with the politically sensitive question of whether to “empty chair” him if, as expected, he refused to attend.

The change will allow Labour to renew their assault on Cameron’s unwillingness to defend his record, and the party is expected to continue to push the Prime Minister to take part. Mr Cameron, however, will be able to say that he was not invited to join the event.

Tonight’s development is the latest in a series of chaotic climb-downs by the broadcasters, who had pledged three debates involving Mr Cameron, and threatened to “empty chair” him if he did not turn up.

Despite the tough talk, it now appears that the BBC, which will begin discussions for the renewal of its Royal Charter with whichever party triumphs in the forthcoming election, does not feel able to go through with the threat.

Negotiations between the broadcasters, led by BBC’s news chief, James Harding, and the political parties, are still ongoing. Those close to the talks caution that there could still be further changes to the proposals.

In addition to the debates, Mr Cameron and Ed Miliband are set be questioned separately by Jeremy Paxman, on Channel 4 and Sky News, while the pair, and Nick Clegg, are to face individual grillings by David Dimbleby in a BBC Question Time-style event.