Shakhtar Donetsk have warned six players who have not returned to Ukraine after a friendly in France that they could face punishment.

Five Brazilians (Alex Teixeira, Fred, Dentinho, Douglas Costa and Ismaily) and Argentinean striker Facundo Ferreira refused to travel back to the Eastern European state which is in the throes of conflict.

It followed the shooting down of flight MH17.

But Shakhtar president Rinat Akhmetov says the players could be punished if they do not return to Ukraine.

"Players have contracts that they have to abide by. If they do not come, I think, they will be the first to suffer," said Akhmetov.

"Hopefully, the mind and heart will prevail over misunderstanding, and the players will not follow temptation and fear. Especially since there is nothing to fear."