A Labour shadow minister has said he was only joking and “joshing around” when he told a friend that his party would lose the general election.

Leaked tapes show Jonathan Ashworth said the situation for the party in seats like Mansfield and Ashfield was “dire” because of a “combination of Corbyn and Brexit”.

But he told BBC News: “I’m joshing around with somebody who I thought was an old friend who’s now leaked it to Guido Fawkes [a blog]. He’s a Tory and we’ve always had a bit of banter together. I’m winding him up, teasing him.”

He added: “We are going to win, we’re going to win this general election, because people are fed up with the Tory cuts to the general election and they’re fed up with the waiting lists going higher and higher.”

Mr Ashworth said he had been made to look like a “plonker” by his friend, a Conservative activist, who sent the tape of their conversation to Tory attack blog Guido Fawkes.

The tapes show Mr Ashworth telling his friend: “They can’t stand Corbyn and they think Labour’s blocked Brexit. I think middle-class graduates – Remainy people – Labour’s doing well among ... but not in big enough numbers to deny the Tories a majority.”

Most polls agree with Mr Ashworth’s assessment, though some point to a possible hung parliament, particularly if tactical voting is taken into account. A pre-election survey of political scientists carried out by the Political Studies Association (PSA) found that academics are divided on whether the Conservatives will win a majority.

Mr Ashworth letter wrote an email to all Labour members to apologise. He told them: “I want to apologise. I’ve made a terrible devastating error which I’m so so sorry for.

“So many of you have been campaigning hard in the rain and cold for me long into dark nights. The fact that you are all working so hard only makes my sense of remorse all the more deeper.”

He added that the leak was a “a Tory dirty trick to try to distract us from our central campaign on the future of the NHS”.

Top 10 marginal seats to watch at the general election Show all 10 1 /10 Top 10 marginal seats to watch at the general election Top 10 marginal seats to watch at the general election North East Fife Currently held by the SNP with a majority of 2 Getty Top 10 marginal seats to watch at the general election Kensington Currently held by Labour with a majority of 20 Getty Top 10 marginal seats to watch at the general election Perth and North Perthshire Currently held by the SNP with a majority of 21 Getty Top 10 marginal seats to watch at the general election Dudley North Currently held by independent, formerly Labour, MP Ian Austin with a majority of 22 LivingInMediocrity Top 10 marginal seats to watch at the general election Newcastle-under-Lyme Currently held by Labour with a majority of 30 Derek Harper Top 10 marginal seats to watch at the general election Southampton Itchen Currently held by the Conservatives with a majority of 31 Rob Candish Top 10 marginal seats to watch at the general election Richmond Park Currently held by the Conservatives with a majority of 45 Robin Webster Top 10 marginal seats to watch at the general election Crewe and Nantwich Currently held by Labour with a majority of 48 Jaggery Top 10 marginal seats to watch at the general election Glasgow South West Currently held by the SNP with a majority of 60 Alec MacKinnon Top 10 marginal seats to watch at the general election Glasgow East Currently held by the SNP with a majority of 75 Christine Johnstone

James Cleverly, chair of the Conservative Party, said of the leaked recording: “This is an honest and truly devastating assessment of Jeremy Corbyn’s leadership by one of his most trusted election lieutenants.

“He admits that Labour has blocked Brexit and that is why voters ‘can’t stand Corbyn’. If even Corbyn’s closest political allies think he is unfit to be prime minister, why on earth should voters be expected to put their trust in him and them?