Britain says nearly 30,000 COVID-19 tests sent to U.S. lab came back void

FILE PHOTO: A member of medical staff is seen holding a testing kit at an NHS coronavirus disease (COVID-19) testing facility in Wolverhampton

LONDON (Reuters) - Nearly 30,000 COVID-19 tests which Britain sent to a U.S. lab for processing came back void, Prime Minister Boris Johnson's spokesman said on Thursday, adding to a mounting pile of questions over the UK's testing regime.

The admission comes in a week where the government has faced criticism by a statistics watchdog over incomplete test data, pressure over turnaround times for test results and teething issues with a new test and trace programme.

Johnson's spokesman said that "operational issues in our lab network" had meant that 67,000 tests were sent to the United States for processing.

"Unfortunately these tests from the U.S. returned a higher void rate than expected. Around 29,500 were returned void," he said.

"Everyone affected was offered a new test immediately. And the lab in the U.S. is not being used for further ... capacity."

The Telegraph, which first reported the story, quoted junior health minister James Bethell as saying Britain had worked quickly to restore its capacity.

"We worked hard to get complete tests for people under difficult circumstances," he told the newspaper.

"In many cases that worked and we are grateful to the team for their efforts. But in some cases it didn't, and the correct judgement was made to void the tests."

On Wednesday, Johnson pledged to make the results of almost all tests for COVID-19 available within 24 hours by the end of this month, although he said there would be difficulties with postal tests.

(Reporting by William James and Alistair Smout; editing by Stephen Addison)