Everton have confirmed the signing of Charlton Athletic winger Ademola Lookman for an undisclosed fee, understood to be in the region of £10m.

The England under-20 international has signed a four-and-a-half year deal which will keep him at Goodison Park until June 2021 and makes him the most expensive League One player ever.

Lookman broke into the Charlton first team midway through last season and has scored seven goals in 25 appearances in all competitions so far this season.

The 19-year-old will go straight to work with the first team and could find himself in the team earlier than expected after manager Ronald Koeman confirmed Yannick Bolaise could be out until 2018 after knee surgery.

Lookman said: “It feels great to be an Everton player.

“As soon as I heard about Everton’s interest I knew this would be the right place for me.

“Everton has a big history and I was also attracted by the manager.

“When you look at what he did at Southampton, and what he does with young players in terms of developing them, that was a big attraction.

“It was great playing in The Championship last season and for the last six months in League One but I feel like I’m ready to make the step up to the Premier League.”

On the signing, Koeman said it was the sort of signing that was in-keeping with the new vision of the club.

“Ademola is a big talent and, at 19 years old, he has a big future in the game. I’m really happy that we’ve been able to bring him here to the club,” said Koeman.

“This is part of the vision we have for the club and it’s important to give to young players the opportunity so that the team continues to evolve and improve.