A Conservative MP and Brexiteer supporter of Boris Johnson has accused the DUP of holding up the UK's exit from the European Union.

Daniel Kawczynski, who is backing Tory frontrunner Mr Johnson to become the next Prime Minister, also said he had "to be careful" when talking about the DUP, whose 10 MPs' votes are keeping the Conservatives in power - at a cost.

Mr Kawczynski told BBC Radio Ulster's Sunday News show that if Mr Johnson becomes Prime Minister, he has an opportunity to win a general election to ensure the Government is "not at the beck and call of the DUP".

"I have to be careful what I say about the DUP because hitherto if I've been critical of them then noises are made back here at Westminster," he said.

"We have still not left the European Union, in part because the DUP absolutely categorically refused to contemplate the Northern Ireland backstop."

He added: "It's a very difficult position for a governing party like mine not to be able to get legislation through without the say so of the DUP and I think with Boris Johnson as leader of the Conservative Party we have every opportunity to win an election in our own right."

The DUP's 'confidence and supply' pact with the Government is due for renewal after the next Conservative leader is in place.

Mr Kawczynski, who has criticised the DUP in the past and accused the party of holding the Government to ransom by opposing the backstop, is a former member of the European Research Group, the Eurosceptic body of Tory MPs at Westminster.

He stood down in April after becoming concerned that a "hardcore element of 'Unicorn' dreamers" was "endangering Brexit" by refusing to vote for Theresa May's withdrawal deal.

In response, a DUP spokesperson said: “The DUP position on Brexit is very clear. We want a deal that respects the referendum result and will protect the economic and constitutional integrity of the United Kingdom. This is something which is widely supported across the benches in the House of Commons.

“We will be unapologetic in standing strong for the people of Northern Ireland.” Mr Kawczynski also suggested that head of the NI Civil Service David Sterling was engaging in “Operation Fear” by warning that a no-deal Brexit would have “grave” consequences for Northern Ireland.

“Nobody knows exactly what will happen if there is a managed no-deal basis, they are speculating and trying to spin the situation,” he said.

Belfast Telegraph