BP said on Tuesday that it had reworked some offshore procedures after workers who had previously been on an unspecified platform in the Gulf of Mexico tested positive for Covid-19.

“BP confirms several workers who had previously been on one of our offshore platforms in the Gulf of Mexico have tested positive for Novel Coronavirus (Covid-19)," the company told Upstream in a statement.

"As a precaution BP has adjusted our mobilisation procedures to further mitigate the possibility of the virus affecting our people and operations. The safety and wellbeing of staff and contractors and respect for the communities in which we operate is our highest priority."

The changes may include rotations with fewer people on schedules and deep-cleaning of BP's four operated offshore facilities of Atlantis, Mad Dog, Na Kika and Thunder Horse, a person familiar with the situation told Upstream.

The workers concerned were also said to be contractors and BP employees.

The incident is the first publicly known case of offshore workers in the Gulf of Mexico province coming down with the coronavirus.

The US Bureau of Safety & Environmental Enforcement oil told Upstream last Friday that no cases had yet been reported offshore in the region, though cases have been seen in the North Sea and off Australia with various precautions enacted in the past few weeks.

A prior version of this story indicated that all of those affected were contractors.