Aston Martin has confirmed Sebastian Vettel is yet to return the negative Covid test required to travel to Saudi Arabia.
Vettel missed the opening race of the F1 season after testing positive for Covid-19.
Nico Hulkenberg stepped in as a last-minute replacement but Aston Martin has revealed the former Renault driver is in Jeddah and is ready to race if Vettel is unable.
Via social media, Aston Martin said: "Sebastian Vettel has not yet returned the required negative Covid test to fly to the #SaudiArabiaGP.
"Nico Hülkenberg will be in Jeddah to deputise for Seb if necessary. We will delay our final decision until Friday to provide Seb every opportunity to race."
Should Hulkenberg take part in the weekend, it would be the fifth time he would have acted as a Covid substitute after replacing Lance Stroll, Sergio Perez twice and Vettel last week.