David Cameron has insisted that he will not back down in his stand-off with the broadcasters of the election television debates.

The Prime Minister insisted that he would not be taking part in the three proposed leaders' debates - including one head-to-head with Ed Miliband - which the broadcasters are planning for the election campaign.

Speaking at a campaign event in Isleworth, west London, he said that he stood by his offer of a single debate with seven party leaders before the campaign got under way.

"I am trying to break the log jam because I am proposing a television debate before the campaign gets under way," he said. "That is my proposal. I won't be changing my opinion about the other proposals."

On Friday, the broadcasters announced that they would be going ahead with the debates regardless of whether Mr Cameron took part, implying that they could "empty chair" him.