Standard Sport understands that Lukaku is on Chelsea coach Antonio Conte's list of potential targets this summer, although it is believed it will take more than the £65m Barcelona paid Liverpool for striker Luis Suarez back in 2014 for the Blues to re-sign the Belgium international.
Lukaku yesterday admitted he wants to be remembered for winning trophies as much as for scoring goals and admitted the best way to showcase his talent is to play in the Champions League.
The 23-year-old's agent, Mino Raiola, had said Lukaku was "99.9%" certain to extend his stay at Goodison Park amid reports of a new five-year deal worth around £140,000 a week.
But Koeman today said: "The (Lukaku) deal wasn't agreed; 99.9 per cent is not 100 per cent and they are still trying to get the contract over the line. That's what I know from the board.
"Of course I am not happy about that interview because, firstly, if Everton is not a club with a lot of ambition, I wasn't the manager in Everton.
"Secondly, and I spoke with Rom this morning, I know it's difficult but if you are a player, prepare yourself to play well and score goals - the rest needs to be done by the manager and the club.
"I spoke with Rom about this project. We had several talks about the future. But I am not so afraid about his situation because the player has two years more on his contract. Of course (I am confident of keeping him) and everybody knows what can happen in football. But you need to respect your contract.
"Every player has ambition, likes to play for titles, play in the Champions League. That's a normal ambition. What we want to do and like to do is to show everyone that if there is one club out of the big six to make the next step then its Everton.
"But it's impossible to do this in one transfer window, and one season. It takes time. But this is a message for everybody; the manager and Everton is trying to get the best team it can. But there is competition."
Everton host Premier League strugglers Hull on Saturday, and Koeman insisted there is no need for Lukaku to miss out on the game following his interview.
"His behaviour, except this interview, is what I like from the player. There is no problem," he added.
"The team needs Rom, and to score goals Rom needs the team. We like to continue and keep the momentum. We are playing well and we know every game is difficult. Last week doesn't count, this is a new game."