Fernando Alonso has been declared "provisionally fit" to take part in this weekend's Chinese Grand Prix.
The McLaren driver, who broke a rib in a crash in last month's Australian Grand Prix, faces further tests before being given the full go-ahead.
The Spanish two-time champion, 34, will be given a second check-up after taking part in first practice on Friday.
Governing body the FIA took six hours to make this decision after testing Alonso on Thursday.
The FIA medical delegate Jean-Charles Piette barred Alonso from racing in the second race of the season in Bahrain two weeks ago because of his injuries.
Speaking before the decision was made public, Alonso said that he felt "100%" but expected the FIA to want to examine him after first practice.
"I guess the normal thing will be after the first session that I feel OK because F1 is a very unique sport," he said.
"It doesn't matter what activity you do before racing, with the unique position I am sitting in, with the G-forces, everything can change in the car.
"So after the first couple of laps I will feel if I am OK from my side. And if it is OK from their side, that is the normal thing or logical thing to follow."
Alonso said he would not have flown to China for the race had he not been confident in his condition.
He spent the weekend in Bahrain working with the team on the sidelines, helping his replacement - reserve driver Stoffel Vandoorne - with his debut.
"If I was not sure, I would not have been flying here," Alonso said. "I did it once in Bahrain and it was quite tough to be there all weekend.
"Last Sunday I took a flight from Milan to Shanghai and I am 100% confident I will be OK."