Ministers are yet to set out details of a Covid testing regime for arrivals from China that comes into force this week, including whether it will apply to people flying from Hong Kong or to those who travelled to the UK indirectly from China. Downing Street confirmed that people flying to the UK from China would need to take a Covid test before travelling, and would not be allowed to travel if they tested positive for the virus. However, on arrival, only an as-yet unknown sample of passengers will be tested, on a voluntary basis, and anyone who is found to have Covid will not be obliged to quarantine. Rishi Sunak’s official spokesperson described the system as “striking the right balance” between monitoring for any potential new variants of concern, while acknowledging that one in 45 people in the UK currently have Covid, and that the main government strategy over the virus was vaccines. While officials confirmed that the new policy would begin as planned on Thursday, the spokesperson said further details of the scheme, including how many passengers will be asked for tests on arrival, and what happens to those travelling from Hong Kong or indirectly from mainland China remained to be decided. “We’re working on the final details of the implementation of the policy,” the spokesperson said. “That includes on Hong Kong and we will update in due course.” The scheme would, he said, be a “precautionary and temporary measure to detect potential new variants of Covid from China”, including a mandatory pre-departure test. Without evidence of a negative test they would not be allowed to board. The spokesperson added that this was separate from the Covid surveillance programme organised by the UK Health Security Agency over potential new variants, involving a “sample of passengers” being voluntarily tested for Covid. The details are being led by the Department for Transport and the Department of Health. A government spokesperson said: “We are working with airlines on the implementation of this policy, and will provide more details in due course.” The decision will affect England only, because travel is a devolved matter. However, all direct flights from China land in England. The order is designed to align with US policy, and is being made because the government believes there is a lack of reliable data from China. Asked on Tuesday if travellers arriving in the UK from China who tested positive for Covid would be required to quarantine, the transport secretary, Mark Harper, told LBC: “No, because what we are doing is we are collecting that information for surveillance purposes. He added: “We manage Covid now by making sure we have got very high levels of vaccination, that is why people who are at risk, older members of the community, for example, should make sure they get their fourth booster shot this winter. That is how we protect people from Covid, that is our primary line of defence. “The policy for arrivals from China is primarily about collecting information that the Chinese government are not sharing with the international community.” Harper, a vocal critic of coronavirus restrictions from the backbenches at the height of the pandemic, said the government had created a “sensible, balanced proposition” to deal with the potential spread of Covid from China. He went on: “This is about a country, China, which isn’t sharing the health data with the global health system that we expect everybody to do. 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.