The Evening Standard reported on Friday that Chelsea were still interested in the Belgium international as Antonio Conte looks to bolster his attacking options at Stamford Bridge.
The same article states that Toffees boss Koeman was preparing Everton for life without their towering striker ahead of a potential return to the west London side this summer.
Lukaku came off the bench to help Everton come from behind and secure a 2-1 victory over West Bromwich Albion at The Hawthorns on Saturday afternoon.
Speaking to the media after Everton’s first Premier League win under the Dutchman, Koeman revealed that Lukaku has decided to commit his future to the Merseyside club.
— Everton (@Everton) August 20, 2016
Lukaku scored 17 times in 37 Premier League games for Everton last season as the Toffees finished in 11th place.
The Belgian forward moved to Everton in a £27m deal from Chelsea in 2013 after Jose Mourinho deemed the striker surplus to requirements.
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