The historic televised leaders' debates were today criticised as a "three-party stitch-up" which excluded key policy areas from discussion.

Green Party leader Caroline Lucas, who is standing in Brighton Pavilion, said a lot of voices had been "silenced" by the failure to include her party and other smaller parties in the debates.

She said this meant voters could not hear arguments about the withdrawal of British troops from Afghanistan and eradicating nuclear weapons, both of which are Green Party policies.

Ms Lucas said she would "fight harder" to be included in the debates at the next election. The historic head-to-heads, seen by millions of viewers, had "an extraordinary influence over the course of the campaign".

She told BBC News: "What they have done is turn a two-party stitch-up into a three-party stitch-up and they have still silenced lots of voices that I believe the British public would have wanted to hear.

"When you had the debates talking about foreign policy, not one of those three parties was talking about withdrawing troops from Afghanistan, which is Green Party policy, not one of them was talking about international development, poverty eradication, getting rid of our nuclear weapons.

"A whole range of different options aren't on the table for as long as you exclude the smaller parties.

"We believe very strongly that if we have those leaders' debates again... they have got to include the smaller parties too."