By Andrew Osborn
LONDON (Reuters) - Prime Minister David Cameron came under concerted pressure on Wednesday from political rivals to join a series of pre-election TV debates he has said he will boycott unless the smaller left-leaning Green Party is also included.
Cameron's refusal has seen opponents accuse him of using a questionable pretext to avoid a debate they say he fears. His foes also accuse him of showing disdain for what they say is a healthy democratic exercise ahead of the May 7 national election, which is expected to be unusually tight.
Cameron, whose right-leaning Conservative Party has little in common with the Greens, has said he wants the debates to happen but that "you can't have some minor parties in and not other parties in".
In separate but almost identical letters, the leaders of the main opposition Labour Party, the anti-EU UK Independence Party (UKIP) and the Lib Dem Party, Cameron's junior coalition partner, wrote to him urging him to reconsider.
"It would be unacceptable if the political self-interest of one party leader were to deny the public the opportunity to see their leaders debate in public," the letters read.
"Therefore, if you are unwilling to reconsider, the three party leaders who have committed to participate will ask the broadcasters to press ahead with the debates and provide an empty podium should you have a last-minute change of heart."
SCEPTICAL
The spat follows a provisional ruling from the broadcast regulator Ofcom saying the Green Party, which currently has one MP in parliament and a small number of local councillors, did not qualify for major party status.
Conservative strategists are thought to be sceptical about any upside for Cameron from the TV debates, fearing they could allow Labour leader Ed Miliband to improve his poor leadership ratings and appear as a credible prime minister-in-waiting.
With the country's mostly right-leaning press regularly deriding Miliband as a socially-awkward nerd, the TV debates are a rare high-profile opportunity for him to prove his detractors wrong, which is why he wants to ensure they happen.
Cameron has less to gain since Nigel Farage, UKIP's media-savvy leader, is targeting Conservative voters in particular and is likely to zero in on him during TV debates. If the Greens were included, Conservatives believe Labour and the Lib Dems would face more robust scrutiny.
Recent opinion polls have shown Cameron's party either narrowly behind or level with Labour.