Manchester United midfielder Marouane Fellaini looks increasingly likely to leave Old Trafford at the end of the current campaign amid interest from Turkish giants Galatasaray and Besiktas and La Liga outfit Valencia.

Fellaini has established himself as an important part of Jose Mourinho's plans, despite being seen as a whipping boy for much of his career at Old Trafford. The former Everton midfielder has proved to be an extremely useful option from the substitutes' bench so far this season, but his recent progress was curtailed by a knee injury sustained on international duty.

The Belgium midfielder's role as a super-sub will presumably continue to prove useful to United in the coming months, but Fellaini is not content with a bit-part position under Mourinho and is reluctant to sign a new deal without certain assurances over game-time, according to The Independent.

The 29-year-old is believed to be on around £120,000-a-week at United, who saw fit to activate a one-year extension on his current contract earlier this year. However he rejected a new contract in September and is determined to play regularly during the latter stages of his career, with his deal at United set to expire in the summer. His situation has not gone unnoticed, with Galatasaray, Besiktas and Valencia all keeping tabs on the former Standard Liege starlet's future.

Galatasaray almost signed Fellaini in the summer, but their attempts to prize the gangly Belgian away from Old Trafford were stopped by Mourinho, who will hope United can thrash out an agreement with his towering lieutenant in the coming months.

Besiktas are another side who were sniffing around Fellaini, and club official Metin Albayrak revealed that the versatile midfielder is one of a number of players the Turkish giants are targeting.

"Fellaini is on our list, we have made efforts to sign him but not just him," he was quoted as saying by "He is not the only player we have scouted."

Fellaini will be able to talk and sign pre-contract agreements with overseas clubs in January, but United are hoping to strike a deal with his camp before then. Talks are still ongoing between both parties.

His future is not United's immediate concern, though, with Mourinho's men instead focusing on clawing back ground on Premier League leaders Manchester City when they face Newcastle United on Saturday (18 November).

Marouane Fellaini
Fellaini is in the final knockings of his current contract at United. Getty Images