Britain is making plans to distribute millions of free coronavirus antibody tests after a version backed by the UK government successfully passed its first major trials, The Daily Telegraph reported on Friday.

The finger-prick tests, which can tell within 20 minutes if a person has ever been exposed to the coronavirus, were found to be 98.6% accurate in secret human trials held in June, involving nearly 300 people and conducted by scientists at Ulster University, the newspaper reported.

It added that the test was developed by the UK Rapid Test Consortium (UK-RTC), a partnership between Oxford University and leading UK diagnostics firms.

Britain’s only antibody tests approved thus far have involved blood samples being sent to laboratories for analysis, which can take days, The Telegraph said.

Anticipating a regulatory approval in the coming weeks, tens of thousands of prototypes have already been manufactured in factories across the United Kingdom, the report added.

Ministers are hoping that the AbC-19 lateral flow test will be available for use in a mass screening programme before the end of the year, the newspaper reported.

“It was found to be 98.6% accurate, and that’s very good news,” Chris Hand, the leader of the UK-RTC, was quoted as saying by The Telegraph.

The tests are likely to be free and would be ordered online instead of being sold in supermarkets, according to plans cited by the newspaper.

“While these tests will help us better understand how coronavirus is spreading across the country, we do not yet know whether antibodies indicate immunity from reinfection or transmission,” a Department of Health and Social Care spokesman was quoted as telling the newspaper.

Britain has so far reported more than 295,000 Covid-19 cases and at least 45,000 deaths, according to the Johns Hopkins University tracker.