Fellaini had 18 months left on his previous deal with Everton, but has now signed a new deal that will keep him at the club until the summer of 2016.
“I’m happy to sign a new deal at Everton. I’ve been here for three-and-a-half years,” he said on Sky Sports News.
“I have a good relationship with the players, the manager, the directors and the chairman, that’s why I’ve signed here.
“It’s a good decision for me. Everton have ambition. Everton has a very good team.
“If Everton didn’t have ambition I wouldn’t have signed here. It is a difficult decision because I know one or two big clubs have been watching me and I had one and a half years left on my contract.
“Everton has a lot of young players with qualities, Jack Rodwell, Seamus Coleman and Ross Barkley.
“They’re the future of Everton, me too I’m young. I’m working hard and training hard, it’s good.”
