Roma forward Mohamed Salah has been ruled out for at least three weeks after suffering an injury to ligaments in his right ankle, the Serie A club announced.

Egypt midfielder Salah, who hit his first league hat-trick for Roma last month, suffered the setback in a training ground clash with teammate Thomas Vermaelen on Thursday.

It means Salah will miss this Sunday's derby clash with Lazio at the Stadio Olimpico, as well as pre-Christmas league fixtures at home to AC Milan, away to Juventus and at home to Chievo.

A statement issued by Roma on Friday said: "On Friday morning, Mohamed Salah underwent further tests which confirmed the original diagnosis.

"Salah will continue working on his recovery plan and should be out for three weeks."

A statement issued earlier said Salah "underwent tests on Thursday that revealed damage to the exterior ligaments on his right ankle, also affecting the front and lateral muscles and tendons."

Salah, who has scored eight league goals in 14 games, is scheduled to play for Egypt at the next African Cup of Nations, to be held in January.