Although this will streamline the security clearance process, it is also likely to spark fears that airport security could be compromised as criminals or terrorists may be able to gather information about security protocols before they are fully vetted.

Although they can be trained, staff will not be allowed to work in the so-called airside part of an airport with access to planes and runways until security clearance is complete.

In the letter seen by The Telegraph, Mr Courts added: “I want to stress that while we are acutely conscious of the need to get more staff into your operations, we have to balance this against the risk of insider threat and other security factors. This will always be our primary focus.”

Aviation bosses and ministers have blamed each other for travel chaos since the start of the Easter holidays.

Referencing and vetting typically requires between 14 and 15 weeks to complete and is performed by a combination of the industry and Department for Transport. But aviation insiders said it is now taking “substantially longer”. Some delays were up to twice as long.

Mr Shapps last week accused aviation leaders of failing to “gear up” for the Easter break after sacking tens of thousands of employees during the Covid crisis, a remark that sparked fury among airline and airport executives.

The vetting is required for employees to receive an airside pass that effectively gives them access to all areas of the airport beyond security scanners.

Referencing of five-year employment records is understood to have been particularly challenging as many applicants have gaps in their career after losing their jobs during the Covid pandemic.

Mr Courts said the Government will explore whether officials from HM Revenue & Customs can conduct employment checks based on tax records instead.

Sir Iain Duncan Smith, the former Conservative party leader said it is “unacceptable” for the Government to blame former EU regulations that it should have changed previously.

“One of the reasons people voted to leave was to get rid of the stupid and overbearing regulations imposed by the EU, yet we keep finding that in so many areas we are still sitting on these same regulations,” he said. 

“This is not the only area where the Government has failed to take action. They have got to make it an urgent matter and stop using it as an excuse.”

A government spokesman said: “Using our post-Brexit freedoms, we are looking at ways to help industry speed up job reference checks. However, we will not allow people to work in the sector when they have not been subject to the appropriate enquiries.”