Testing kits heading to the UK have been found to be contaminated with COVID-19.

Laboratories across the country were warned to expect a delay after traces of the virus were detected in the test kits.

This comes as public health officials face criticism over why Britain’s testing capacity is lagging behind other countries, including Germany, South Korea, and the United States.

In an effort to boost the tests to 25,000 every day by the end of April, the government asked private companies to help with test production.

One of the suppliers – the Luxembourg-based firm Eurofins – sent an email to government laboratories in the UK warning that a delivery of key components called “probes and primers” had been contaminated with coronavirus and would be delayed, the Telegraph is reporting. 

The firm admitted there had been “an issue” and insisted other private providers are suffering from the same problem.

How the contamination occurred has not been detailed, but senior health officials are confident that the delay in testing will not have a significant impact on the country’s testing efforts. 

Meanwhile, the news of contaminated tests comes amid controversy surrounding how much testing the UK is doing.

Cabinet minister Michael Gove initially said that the UK had met its testing target for the coronavirus and that 10,000 tests were done on Mar. 29.

But Public Health England later released figures showing that only 8,000 tests were conducted in the previous 24 hours despite the fact that the NHS has capacity for more than 10,000.

University College London Professor Anthony Costello told BBC Radio in an interview that the UK isn’t using its resources as efficiently as countries like Germany – which is handling more than 70,000 tests per day.