Jacob Rees-Mogg has admitted he was wrong to say there would be no delays at the port of Dover caused by the UK leaving the EU.

But the Brexit opportunities minister maintained the government line that the French, not Brexit, had caused the recent delays, in a radio interview on Tuesday.

LBC radio replayed a claim from 2018 when he insisted “there will be no need for checks at Dover” and he was clear that “the delays will not be at Dover, they will be at Calais”.

Rees-Mogg blamed Paris for the “French-created delays” witnessed recently before he was asked if he would apologise for getting it wrong.

“Yes, of course I got it wrong, but I got it wrong for the right reason, if I may put it that way,” he said.

“The point I was making was that the only delays would be caused by the French if they decided not to allow British people to pass through freely. They have decided to do that.”

Rees-Mogg went on to suggest that Britons might believe “going to Portugal is more fun because the Portuguese want us to go and the French are being difficult”.

“Why should we go and spend our hard-earned money in France if the French don’t want us?” he asked, before insisting he was not calling for a boycott.

Authorities in Dover declared a critical incident as gridlock meant delays of up to five to six hours and volunteer staff handing out water in bumper-to-bumper traffic.

Both Port of Dover and Eurotunnel, which operates rail and car rail transportation across the Channel, have said the delays were caused by the extra checks needed on British passports.

Under the Le Touquet agreement between France and the UK, French border control staff are stationed on the British side of the Channel.

Before Brexit, when freedom of movement existed for EU nationals, officials were required to only check passports for identity purposes, matching the faces of the people in cars with their passports and ensuring the document was in date.

Since Brexit, different travel rules apply for all third-country nationals.

British nationals can still travel visa-free to the EU but only for a 90-day period in any 180-day period.

That means officials at French border controls must stamp each passport to record entry and exit and also check the passport for previous stamps to ensure the 90-day limit has not been breached.

Port of Dover said two weekends ago it resulted in checks taking an average of 90 seconds compared with 48 seconds before Brexit.

The authorities admitted that there was also a problem with a shortage of staff for hours on the Friday, 22 July, but this lasted only about two hours.

Port of Dover had increased its number of passport-checking booths from six to nine in June to prepare for the weekend of 22 July. It was the weekend after schools in England broke up for the summer holidays, traditionally the busiest days for tourist travel.

Last weekend, Dover carried 142,000 passengers – a fivefold increase on this time last year. Eurotunnel carried about 100,000 passengers.

The extra passport checks combined with the huge spike in traffic resulted in queues of up to six hours before travel times returned to normal on Monday 25 July.

The travel industry is warning that delays could be even worse for travellers after the EU introduces biometric controls including face recognition and fingerprinting next summer under the so-called Entry Exit System (EES).