Media playback is unsupported on your device Media caption The DUP's Nigel Dodds said the BBC Trust's decision 'defies belief'

The BBC Trust has rejected the Democratic Unionist Party's (DUP) appeal to take part in TV debates ahead of the general election.

The party's deputy leader Nigel Dodds said the trust's decision "defied belief".

The DUP has already begun legal action against the BBC for excluding it from its earlier proposal of two TV debates.

Senior DUP members met BBC management in Belfast last week to complain about being omitted from the network debates.

Mr Dodds said the process had been "shambolic from the start".

"The BBC has not engaged with us in a constructive manner," he said.

'Big mess'

"As an entirely predictable result, their management of this process has descended into chaos. This incompetence in organising these debates shows conclusively that they cannot be left to the broadcasters to arrange."

He said the broadcasters had "made a big mess" of the situation and that an independent commission should be brought in to organise TV debates in the future.

He added that the DUP remained "keen to ensure Northern Ireland's voice is heard in any national debate that may take place".

The decision means the party is now likely to begin a judicial review against the BBC.

Image copyright Getty Images Image caption The DUP has more MPs than four of the seven UK parties invited to take part in the TV debates

The parties invited to take part in the debates are the Conservatives, Labour, Liberal Democrats, UKIP, SNP, Plaid Cymru and the Greens.

The DUP is the biggest party in Northern Ireland and the fourth largest party in the House of Commons.

With eight MPs, the DUP has more members elected to the House of Commons than four of the seven parties that have been invited to participate.

The BBC said that its impartiality is crucial and network TV debates could not include "just one" party from Northern Ireland.

In its findings, the BBC Trust said that the corporation was "reasonably entitled" to take the view that the SNP and Plaid Cymru were not comparable with the DUP, on the basis that "the SNP and Plaid Cymru compete directly for votes with the larger parties of Great Britain, whereas the DUP and the other NI parties do not".