Fernando Alonso will return to Formula 1 "if Mercedes or Ferrari" come knocking.

That is the view of Flavio Briatore, the former F1 personality who is still involved with the retiring Alonso's management.

A fantasy market

Spanish sports newspapers quote the Italian as saying: "If there is an offer from Mercedes or Ferrari, would he come back? I think so.

READ: Fernando Alonso not ruling out F1 return for 2020

"I cannot know, but in a fantasy market, I think so," Briatore added.

He said those top two F1 teams are the only ones that could tempt Alonso back to a sport that clearly frustrated the 37-year-old in the end.

"There are only two teams. The only other solutions are to finish fourth, fifth or sixth," said Briatore.

'We will see what happens'

"I think with the talent he has, you put him in the right car and he could still be the strongest driver along with Hamilton.

"We will see what happens in a few months or a year," he added.

"He wants a rest, and I think after so many years many like Prost did it as well. Now he needs a period of relaxation.

"He had frustrating years with a ridiculous performance by McLaren but Fernando always behaved impeccably and drove beyond the highest level," said Briatore.