Rishi Sunak accused Sir Keir Starmer of ducking TV debates because he lacked courage and “doesn’t have a plan” for the country.
The Prime Minister claimed Sir Keir did not want to take part in weekly debates throughout the General Election campaign.
Televised leaders’ debates first featured in the 2010 campaign, when there were three, but the Tories are reportedly pushing for a record six this time round.
Labour sources indicated Sir Keir would be willing to take part in the two debates with the largest audiences – BBC and ITV.
But the sources said they would not agree to “tearing up” the format established in previous elections “just to suit this week’s whims of the Tory Party”.
Writing for The Telegraph, Mr Sunak said: “There are big issues at stake in this election. Do we continue cutting taxes or raise taxes on working households as Labour would do?
“Do we prioritise energy security and your family’s finances in our approach to net zero or put environmental dogma first as Sir Keir Starmer and Ed Miliband would. And, above all, how do we give this country the secure future it deserves?
“I want to debate these issues with Sir Keir Starmer. But he doesn’t want to because he doesn’t have a plan and doesn’t have the courage to say what he wants to do.”
Tory chairman Richard Holden told the Daily Express: “It’s no surprise spineless Sir Keir Starmer is now chickening out of debates that he publicly promised to do just months ago.”
Sir Keir said in January that he was “happy to debate any time” with the Prime Minister.
Labour sources said Sir Keir will speak with voters and take questions from the media throughout the campaign.