Media playback is unsupported on your device Media caption Nick Clegg and David Cameron had just answered questions from the public

Nick Clegg has laughed off unguarded comments to David Cameron that they agree on too many things as "banter".

The deputy prime minister made the jokey aside at the end of a question and answer session - but it was picked up on a microphone he was wearing.

He told the PM: "If we keep doing this we won't find anything to bloody disagree on in the bloody TV debate."

He admitted to BBC Radio Sheffield that he was embarrassed by the remark and the press coverage it had received.

"Yeah, I cringed when I saw it," Mr Clegg said.

"It just shows you can't afford to make tongue-in-cheek remarks with a microphone on your lapel. I mean, look, it's just a bit of banter."

Public fights

At the end of a public meeting at the Boots factory in Nottingham, Mr Cameron told their audience that the event may have been "a bit better natured between the two of us" than the TV debates would be during the 2015 election campaign.

But as the two men walked out of the meeting together, Mr Clegg began chatting privately to Mr Cameron, apparently forgetting that his TV microphone was switched on.

The Lib Dem leader has resisted calls from some in his party to pick more public fights with the prime minister to assert his independence.

But his unguarded comment suggests he is anxious not to appear too close to the Conservative leader when the two take part in the expected televised debates at the next general election.

Mr Clegg agreed with Mr Cameron on every subject that was raised in Thursday's question and answer session - from Libya to NHS reforms - apart from May's referendum on changing the voting system, on which they have agreed to differ.

Mr Clegg also came to the defence of Chancellor George Osborne's cut in fuel duty - and insisted it was part of a wider government strategy to boost the economy.

He said: "We just hope all of these things, when you put them together will get the wheels of the economy really moving again but also crucially will help people as they face these difficult times and these high costs."

Mr Clegg and Mr Cameron - who famously cemented the coalition agreement with a joint press conference in the Downing Street rose garden in May - have both continued to hold their own public meetings around the UK.

They have rationed joint appearances like the one at the Boots factory amid concerns among their backbench MPs and grassroots members that they are too close and will struggle to establish separate identities at the next election after working together for so long in government.

Earlier this month, Lib Dem president Tim Farron warned the party was in danger of losing its identity in coalition with the Conservatives - and urged Mr Clegg to take a "spikier" approach towards Mr Cameron by playing up policy differences between them.