Travellers testing positive for Covid after arriving in the UK from China will not be forced to quarantine, a Cabinet minister said.

Transport Secretary Mark Harper said the move to test those coming into the country on flights from China is about “collecting information” due to the Beijing government refusing to share its own coronavirus data.

The senior Conservative MP’s comments confirmed details reported by The Independent.

Testing will be voluntary for those arriving at Heathrow – the only UK airport with direct flights from China reportedly offering tests, the news site also said.

Mr Harper, asked if those who test positive after arriving in the UK will be required to quarantine, told LBC: “No, because what we are doing is we are collecting that information for surveillance purposes.”

He said there are “very high levels of vaccination” in the UK and encouraged older, more vulnerable people to “get their fourth booster shot this winter”.

The Cabinet minister, who campaigned against stringent restrictions from the backbenches during the pandemic, added: “The policy for arrivals from China is primarily about collecting information that the Chinese government is not sharing with the international community.”

Under measures announced by Health Secretary Steve Barclay, passengers flying from China into England from Thursday will be required to take a Covid test before boarding a plane.

The Government will also carry out surveillance testing of a sample of passengers to try to spot new variants of the virus which could pose a threat.

The Prime Minister’s official spokesman said the Government would set out the full details regarding new rules for travellers entering the UK from China “in due course”.

But they rejected any suggestion that the new rules for Chinese travellers could signal a wider change for visitors travelling to the UK from countries with high rates of Covid-19.

He said: “A part of the reason for this was because of a lack of comprehensive health information being shared.

“We’re working with the Chinese government to encourage them – we’re not alone in this – to get more information from them.”

There are no direct flights from China to Scotland, Wales or Northern Ireland but ministers said they are working with the devolved administrations to implement the measures UK-wide.

The move comes as Beijing prepares to start reissuing passports and visas for overseas trips after lifting its zero-Covid controls — a decision that has lead to a massive surge in infections.

Mr Harper called Prime Minister Rishi Sunak’s approach a “sensible, balanced proposition” to deal with the potential spread of Covid from China.

“This is about a country, China, which isn’t sharing the health data with the global health system that we expect everybody to do,” he told LBC.

“That is why we have put this temporary precautionary measure in place as China opens up its borders.

“We are doing two things: we are requiring people who fly from China to have a pre-departure test so they have got to show that they are negative before they get on that flight, and when they get to the United Kingdom, the UK Health Security Agency will take a sample of passengers and test them.

“That is so that we get that information into our health system and we can track the virus that is coming from China.

“That, I think, is a very sensible, balanced proposition which I think helps keep people in the UK safe but doesn’t put any restrictions on how people in the UK are able to operate.”

The Department of Health and Social Care (DHSC) said passengers “will not be allowed to board a flight” to the UK from China if they do not have “evidence of a negative test result”.

The testing is optional and people can decline if they wish to do so

But, in a separate statement, a DHSC spokeswoman confirmed that tests upon arrival in England were “optional”.

She said: “We encourage people at the border to take a test to help themselves, their families and wider knowledge on Covid.

“However, the testing is optional and people can decline if they wish to do so.”

Beijing has condemned the introduction of Covid-19 testing on passengers arriving in countries such as the UK from China.

Chinese officials said that “entry restrictions adopted by some countries targeting China lack scientific basis” and that the country could impose counter-measures.

Some experts cautioned that the wider issue of testing arrivals was not straightforward.

Prof Thomas House, an expert in mathematical statistics at the University of Manchester, suggested that “any contribution of the Chinese epidemic to what we see in the UK is likely to be minimal”.

He said that the on the “complex” issue of surveillance testing, “it is worth noting that the capacity for such surveillance is always limited”.

Testing travellers, he said, needs to be balanced against “potential enhanced surveillance in our health and social care sectors”.

Prof Rowland Kao, from the University of Edinburgh, said that the surveillance testing could fill an “important gap”.

Prof Kao, an expert on veterinary epidemiology and data science, said: “Testing on arrival is not to prevent spread but to gather data – we know very little about what is happening in China.

“If we and other countries are able to in particular gather viral sequences, this will give us knowledge of what variants might be emerging in China.”