London - Everton have broken their club transfer record on Wednesday when they paid £28 million to sign Belgium striker Romelu Lukaku on a five-year deal from Premier League rivals Chelsea, the club announced.
Lukaku finished as Everton's top scorer last season after finding the net 16 times in 33 appearances while on loan at Goodison Park, helping Roberto Martinez's side to a fifth-place finish in the Premier League.
The 21-year-old played for Belgium at the World Cup, but his chances of establishing himself at Chelsea were hindered by the arrival of Diego Costa from Atletico Madrid and the return of veteran striker Didier Drogba.
"I am really excited about rejoining Everton. I had a fantastic experience last season and a great relationship with the manager, the chairman, the staff, the players and the fans. I can't wait to get started again and I'm looking forward to a successful season," said Lukaku.
Martinez told the club's official website that the signing was an indication of the club's ambitions despite Everton struggling in recent years to match the financial muscle of their Premier League rivals.
"Welcoming Romelu Lukaku back to Everton on a permanent basis is the news that all Evertonians wanted to hear," said the Everton boss.
"We know that Romelu is still a young man and the potential that he has is quite unique, and we are desperate to see him enjoying his football and to watch him grow as footballer in the years to come.
"The arrival of Rom is more than just a signing, it's the fruition of a lot of hard work to get the player we wanted. This is a big moment for Everton's history and the perfect way of getting the squad ready for the start of the season."
An established Belgian international with 32 caps, Lukaku shot to prominence while a teenager at Anderlecht before earning a move to the Premier League with Chelsea in 2011.
A loan spell at West Bromwich Albion followed 12 months later before he arrived at Everton during the final minutes of the August 2013 transfer window.
Martinez admitted earlier in the day a centre-forward was an area he had prioritised since the end of last season.
"We clearly need to strengthen in the number nine position, the striker, and probably another attacking player," he said.
"There is not an anxiety at finding out who the strikers will be. We need up to three attacking players and that is bearing in mind the different ways we are going to play and attack.
"We know exactly our priorities and the names. We will work hard to get them but they need to be a perfect fit. Every player that comes in needs to add to what we already have," he added.
"We are not going to bring in players for the sake of it, it will be the ones we need.
"The dressing room is something special and my only worry is bringing in a player who could disrupt that."
Everton open their Premier League campaign at promoted Leicester City on August 16.