The 30-year-old France international was hurt when he collided with Roma's Rodrigo Taddei in Inter's 2-1 second leg defeat, which saw them beaten 7-4 on aggregate by their Serie A rivals.

Vieira, who has only recently come back from a troublesome right hamstring injury for which he had surgery, could now be a doubt for France's Euro 2008 qualifying matches at home to Ukraine and Georgia on June 2 and June 6.

France are tied on 12 points with Ukraine and Scotland at the top of Group B, but have a game in hand on the Scots. Italy are fourth in the group on 10 points, and like France have played five matches.