Mitrovic has had his head turned due to interest from Saudi Arabia where Al Hilal are keen to sign him.
He has already agreed personal terms on a three-year deal with Al Hilal and is pushing for the move to the Middle East this summer.
However, Fulham rejected their €30m offer recently and have made it clear that they do not want to sell the forward.
But Al Hilal have received encouragement from the player and are claimed to be ready to put in a second bid.
The Saudi Arabian club are pushing to sign the Serbian forward in the ongoing transfer window.
They are prepared to test Fulham’s resolve by offering more money for the 28-year-old striker this summer.
Al Hilal recently signed Sergej Milinkovic-Savic and are now eyeing uniting him with his Serbia team-mate Mitrovic.
It remains to be seen whether Fulham can stick to their stance in the face of another big offer.
