Everton manager Ronald Koeman has revealed that contract negotiations are still ongoing with key midfielder Ross Barkley, but is hopeful of reaching an agreement prior to the summer transfer window.

The Dutchman has already given the academy product an ultimatum regarding his future at Goodison Park, warning that he will be sold at the end of the season if he fails to put pen to paper on a new deal.

Romelu Lukaku has made it clear that he will not thrash out fresh terms with the club, meanwhile, as he is looking to further his career by moving to a side that can offer Champions League football, and Koeman is putting those discussions to one side.

"[Lukaku] told me that he will not to sign a new contract," he told reporters. "I leave it now because I can't change that situation at the moment. It's better to focus for the weekends and we will see what happens at the end of the season."

Asked for an update on how talks are progressing with Barkley, he added: "I'm not involved in the negotiations, but I know that the board is talking to [Barkley's] agent. "I don't know [what stage negotiations are at]. It's not about one week, but of course we need to know the answer before the end of the season.

"Yes [everything is being done to keep Barkley], but it's always about the contract. We will offer him the contract, what is good, what is normal, what the player is. I think how he's improving this season, Everton is the best place for him to continue.

"I spoke to Ross several weeks ago and he mentioned his ambition – Champions League. I told him I had the same ambition and I think we are going in a good direction. He is one of the key players, he's kid of the club, kid of the town. In my opinion, there is no better place for him to continue football than in Everton."

Barkley has been linked with Tottenham Hotspur in recent weeks, while Chelsea are the strong favourites to land their former player Lukaku.