Lyon president Jean-Michel Aulas admits it will be difficult for the club to keep hold of their star players this summer - amid reported interest from Chelsea in Moussa Dembele. 

The Blues reportedly set their sights on a move for Dembele in the January transfer window, with boss Frank Lampard keen to sign another striker to provide competition for Tammy Abraham upfront.

Aulas subsequently issued a clear hands-off warning to Lampard and co, however, insisting the player was not up for sale in the winter market.

Yet the Lyon chief has opened the door for Chelsea to come back in for Dembele when the summer transfer window opens.

Aulas has admitted that it will be tricky for the Ligue 1 side to keep hold of their key men, which comes as a major boost for Lampard.