The two men agree there are many similarities between them

In a special edition of Question Time, Nick Clegg and Chris Huhne agreed that it had been a tough time for the party, but now was the time to unite.

Mr Clegg said he had already had private conversations with Sir Menzies Campbell and Charles Kennedy.

Mr Huhne said it would be foolish not to make use of men of their "calibre".

Sir Menzies became Lib Dem leader early in 2006 after Mr Kennedy - the party's most electorally successful leader for 80 years - was forced out after a rebellion by members of his front bench team, after he admitted a drink problem.

'Damaging' departures

Sir Menzies' resignation in October came as a surprise to many of his colleagues. But he has denied claims he was forced out and said he had decided to leave because of continuing questions about his age and leadership.

In their first televised debate, Mr Clegg and Mr Huhne were asked whether the manner of their predecessors' departure had been damaging to the Lib Dems' reputation.

When you have two people of the calibre of Charles and Ming it would be foolish of any leader not to bring them in and use them as part of a team, absolutely on the front line Chris Huhne

Mr Clegg replied: "Yes, I should think so", but said it was now the time for the party to create a sense of "unity and momentum" and reach out to new voters.

He said he had been in private conversations with Mr Kennedy and Sir Menzies and added: "If they want a big job in my shadow cabinet I would be absolutely delighted."

'Rough time'

Mr Huhne agreed it had been a "rough time" and paid tribute to work done by Sir Menzies.

Sometimes similarity is a good thing Nick Clegg

He said the party was blessed with a "tremendously talented front bench" but added: "When you have two people of the calibre of Charles and Ming it would be foolish of any leader not to bring them in and use them as part of a team, absolutely on the front line. That would be my intention and hope."

Mr Huhne also denied that a previous comment about not being "David Cameron's stunt double" was a swipe at Mr Clegg, saying he was thinking of "a general direction of the party... we must never in the Liberal Democrats try and mimic either the Conservatives or Labour".

Asked about claims he had accused Mr Huhne of making "headline grabbing announcements" last year, Mr Clegg said it was "hauling up quotes from last year or the year before" was irrelevant and completely out of context.

During the head-to-head debate both men agreed there were not many differences between them and paid tribute to each other at the end. Mr Clegg added: "Sometimes similarity is a good thing."