Len McCluskey: Labour race boring without Jeremy Corbyn

Jeremy Corbyn (right) is campaigning on an anti-austerity agenda

The leader of the UK's biggest trade union has told the BBC the Labour leadership race would be boring - if left-winger Jeremy Corbyn wasn't in it.

Unite's Len McCluskey said "an enormous surge" of people wanted to take part after Mr Corbyn was confirmed as running "because people are inspired".

Mr McCluskey accused the "ruling elite" of "trying to rubbish" Mr Corbyn.

The veteran only got enough support to enter the race thanks to some MPs wanting "to broaden the choice".

"Unite have already signed up 50,000 affiliate supporters to Labour and they are joining every day. And we will be doing a lot more than that," Mr McCluskey told BBC Radio 4's The World Tonight.

He said that those who thought Mr Corbyn was "marginalised" should "watch this space".

"I know the people who will be uncomfortable, despite the fact that they are saying the opposite - and that's the ruling elite," he said.

"They try and rubbish it, they try to turn it into a joke, but secretly they will be worried sick that ordinary people are suddenly given something to inspire them and something to link onto," Mr McCluskey said.

Len McCluskey says members are signing up to vote

Asked explicitly if the Labour leadership race would have been boring without Jeremy Corbyn in it, the Unite leader shouted: "Yes."

Despite only getting enough MPs to back him with minutes to spare before the nomination deadline last month, the momentum Mr Corbyn's campaign is gathering is worrying some within the party - who wonder how a strong performance from him might be perceived by the wider electorate.

On Friday, a newsletter sent by the group Labour First appealed to supporters of Andy Burnham, Liz Kendall and Yvette Cooper not to endorse Mr Corbyn in any way.

Luke Akehurst, the group's secretary, said: "We clearly do not share Jeremy Corbyn's politics and believe these would destroy Labour's chances of electability."