David Cameron has told ITV News he will not take part in TV debates before the general election unless the Green Party is also included.
His comments follow Ofcom announcing that the Green Party, which has more than 27,000 members and is currently polling at eight per cent nationally, does not have "major party status" in the general election.
The watchdog has only made an initial view, but it will weaken the Green Party's case to be included in the debates. Ofcom will make a final decision in March and the format of the TV debates remains the subject of much wrangling between political parties and broadcasters.
While rejecting the case for the Green Party and Northern Ireland's Traditional Unionist Voice (TUV) being added to the list of major political parties, Ofcom ruled Ukip should be added on the list.
Now Cameron has told ITV's political editor Tom Bradby he would not "go in" to the debates unless the Greens did too.
In response Green Party leader Natalie Bennett said:
Obviously David Cameron has his own political interests but I think we should give the Prime Minister credit for recognising that the debates would be unbalanced and bad for British democracy if Ukip is included and the Green Party excluded.
Nick Clegg, however, publicly accused Cameron of "making excuses" not to participate in the TV debates.
If the Greens are not given major party status by Ofcom it will also affect the number of broadcasts they are allowed to make during the general election campaign as well as the amount of TV and radio coverage they are entitled to.