In a letter to the Competition and Markets Authority (CMA), Javid said a “rapid high-level review” was needed to protect holidaymakers.

NHS PCR tests can only be used if someone displays symptoms and cannot be used by travellers to prove their Covid status before or after travel.

Private PCR tests cost around £75, on average. However, some people have reported being charged hundreds of pounds.

In the letter to CMA chief executive Andrea Coscelli, Javid said: “The cost of PCR testing can act as a barrier, especially for families who want to travel together.

“It is not right if some families experience yet further disruption unnecessarily because of practices in the market for private travel tests.

“It is for these reasons that I am writing to you to ask you to conduct a rapid high-level review of the market for PCR travel tests to assess what action might be taken to ensure that consumers do not face unnecessarily high costs or other poor provision.”

Javid also tweeted: “People should be able to go on holiday, whether it’s to see family or just to relax, without fearing excessive fees for PCR tests.”

Consumer group Which? has warned private testing for travel was “prohibitively high” in the UK.

Which? travel editor, Rory Boland, said: “Currently, an unvaccinated traveller on a return trip to Spain requires four tests totalling an estimated £219 per person, and even if you are vaccinated it’s still close to a hundred pounds. Much of that cost is because of the high price of tests in the UK.

“While it is positive that the Competition and Markets Authority has been asked to examine the Covid test market, it is disappointing that it has taken so long for this issue to be investigated.

“The government must take action to ensure private testing for travel is affordable for all UK consumers – not just those who are better off.”

A CMA spokesperson said: “We are aware of concerns about the evolving markets for COVID-19 tests for international travellers. We look forward to providing the Secretary of State with advice on how best to ensure that travellers have access to tests that are affordable and reliable.”