The Brexit Party is the only party with a chance of toppling Labour in its South Wales heartland, Nigel Farage has said.

The Brexit Party leader told supporters in the Welsh town of Pontypool that his party could beat Labour in the General Election if Boris Johnson reverses his decision not to enter into a “Leave” pact for the poll.

On Friday, Mr Farage said in a speech traditional Labour voters who also voted to leave the EU would be choosing to scrap Brexit if they supported Jeremy Corbyn’s party on December 12.

Mr Farage said: “There were five million people that voted Brexit, then voted Labour in the 2017 general election.

“Here in South Wales so many constituencies voted leave and now have a Remainer MP. An MP that wants to put a second referendum to the people with not really much of a choice.

“The choice Mr Corbyn wants to give us is Remain versus a new form of Remain. Labour will crush the result of that referendum.”

Mr Farage, who was joined by Brexit Party MEPs Nathan Gill and Ann Widdecombe and Welsh Assembly member Mark Reckless, warned Mr Johnson that the Tories stood no choice of beating Labour in South Wales constituencies like Torfaen, and urged him not to split the Brexit vote.

Mr Farage said: “In Torfaen and other constituencies in South Wales the Conservatives haven’t won for a hundred years. And they are not going to win here on December 12. There is no chance of them winning.

“So I would make this urgent plea to Boris Johnson and others: don’t split the Brexit Party vote here in South Wales, we are the challengers to the Labour Party. We will beat Labour in many of these constituencies.”

After his speech the Brexit Party leader, who is not standing as a candidate in the General Election, challenged the Prime Minister to a one-on-one televised debate about Brexit.

He told the PA news agency: “I’ve been very struck that over and over that the Prime Minister says its a fantastic deal, but when asked about the content of it he seems to struggle a bit.

"He seems to struggle with the concept that Northern Irish exporters are going to need to fill in customs forms. He made an explicit pledge in the House of Commons that we get back control of our fish stocks, but we don’t.

“I think before the public are bamboozled into accepting that this is Brexit, we want to debate it.

“I’m convinced it’s not Brexit and certain it doesn’t get Brexit done, and I think an open debate on this would be a good thing.”

Referring to the Tories refusing to enter into an agreement with his party, Mr Farage said: “It’s not too late for Boris. He hasn’t launched his manifesto, a General Election is a chance to press the reset button. I’d love to see him move from where he is.”