Lukaku's agent offers no guarantees over his long-term future despite new deal
Romelu Lukaku's agent Mino Raiola claims a new contract is "99.9 per cent" done but offered no guarantees the striker would stay at Everton long-term.
The Belgium international, whose current deal runs until 2019, is set to become the club's first £100,000-plus-a-week player.
Everton fended off interest for the 23-year-old in the summer but Raiola said a new contract would not prevent him leaving at the end of the season.
"With Everton, we have 99.9 per cent reached terms," he told talkSPORT.
"We are talking to the club in a good spirit so we are very hopeful. There are no problems on the way that I foresee.
"I don't see any big problems. It is a question of putting the details on the paper."
Lukaku joined the Toffees from Chelsea for a club-record £28million in 2014 and has scored 70 goals in 142 appearances, last season becoming the first Everton player since Gary Lineker to score 25 league goals in a single campaign,
That form attracted interest from a number of clubs but Everton were able to resist advances and persuade Lukaku to stay to work under new manager Ronald Koeman.
However, there is likely to be a repeat at the end of this season and Raiola gave no assurances the outcome would be the same.
"If Romelu is good enough, strong enough, to move in the next year then we will talk to Everton about it," he added.
"It is a very good relationship at the moment. We know what both parties want.
"Everton is going through a transition from a club that was maybe aiming for Europa League and now they are more ambitious and maybe in the near future will go into the Champions League or maybe even win the Premier League at a certain stage.
"In football, you can't look too much in front. You need to take it one transfer window at a time.
"For now, we are agreeing terms and then we will see in the summer what happens and how the situation is.
"If there is an interest from both parties to move on, then we will talk with the club, but at this point we only have one objective and that is to perform as well as possible for Everton."
Koeman is confident he will receive backing both in terms of finances and time to lift Everton to the level Raiola hopes they can attain.
The Dutchman is keen to revamp the playing staff he inherited from predecessor Roberto Martinez in the summer and will use the next two transfer windows to strengthen, while also moving on players who do not fit into his plans.
Koeman's long-term plans have already started to take shape, with senior players Leighton Baines and Gareth Barry - plus youngster Mason Holgate - signing contract extensions last week and in addition to Lukaku there are plans to begin negotiations with midfielder Ross Barkley early in 2017.
Koeman, backed by billionaire majority shareholder Farhad Moshiri, will spend in January, with Manchester United duo Morgan Schneiderlin and Memphis Depay targets, but he accepts that is only the beginning.
"We know that due to the people we have inside the club that this is a project which is for the long term and it does not mean that you are fighting for trophies within six months of arriving at a new club," he told Dutch broadcaster NOS.
"We need to invest not only in January, but also in the next summer transfer window.
"I believe that the club are aware of this and that I will receive the time. But it is not easy to get time within football these days."