Ferrari and Mercedes have been warned about a breach of the strict coronavirus measures in force for the back-to-back races in Austria.
While most of the paddock remained in their 'bubbles' between the first and second race weekends, it emerges that Charles Leclerc and Valtteri Bottas each travelled back to Monaco earlier this week.
"I was tested twice before returning," Leclerc, who was photographed out for dinner with his girlfriend and another person without wearing a mask, insists.
And Bottas is quoted by Finnish media: "It makes no difference if I stayed here with the team or returned home. In terms of safety, there is no difference at all."
However, an FIA spokesman insisted: "We have issued a warning.
"Any further breaches will be referred to the stewards."