The Nigerian front man was given a work permit at an appeal hearing in Sheffield, after his original application following his move from Middlesbrough was rejected because he did not meet the criteria by appearing in 75 percent of international matches played in the last two years.

But Yakubu was initially going to be part of a double Everton signing, with Moyes having agreed a deal to acquire midfielder Manuel Fernandes last weekend.

In the complicated negotiations for the Portuguese star, Everton had offered a £6m fee for the player who was 50 percent owned by a third party company.

When the Premier League questioned that deal, Everton raised the money to buy the player outright for £12m.

But Fernandes pulled out last weekend and joined Valencia instead, and now Everton still have that £12m in their kitty.

Moyes desperately needs another midfielder now, and has been linked with Bolton's Kevin Nolan, Fulham's Papa Bouba Diop and Fenerbahce's Ghana captain Stephen Appiah.

Everton have made an enquiry for Appiah and been told he is not for sale, which leaves Moyes scouring the market for a new midfielder before the transfer window slams shut on Friday.

But at least the acquisition of Yakubu will solve his striking problems, after selling James Beattie to Sheffield United despite having youngsters Victor Anichebe and James Vaughan injured.

Moyes said upon the arrival of Yakubu, who could make his debut at Bolton on Saturday: "He has a very good goal scoring record in the Premier League and he also offers strength and power. We hope he continues his good scoring record with us.

"We have some good strikers in our squad already and he adds further depth and quality to our squad."

Yakubu, 24, has signed a five-year deal, with the Home Office being convinced at the hearing that he was a proven top-line Premier League player over the last four years.

He failed the international criteria because he had fallen out with the Nigeria coach and not been selected on a regular basis over the past two years.

Work permits cannot be transferred from club to club, and a new application must be made ahead of each move.

Yakubu is the club's record signing, surpassing the £8.6m paid to Crystal Palace for Andrew Johnson last year.

As Everton's fourth major signing of the summer, he revealed his delight at the move to evertonTV:

He said: "I am happy to be here. It is a great feeling to meet a lot of good players and see the spirit that they have.

"I have always said that I want to play for a club that plays in Europe and I think they have the ambition to move forward. They want to finish in the first four and the Champions League and play in the UEFA Cup, and for me that is my dream.

"I know there is a long way to go and I want to be part of that, to be successful and to have that dream.

"I chose to go to Middlesbrough because they were in Europe. At the moment they are not doing it. I think I made the right decision to come to this place. It is a massive club and it is a great feeling. There are great players and you want to play for a big club."

Yakubu boasts an impressive goal scoring record, with only Thierry Henry having netted more Premier League goals in the last four years.

He began his career in England with Portsmouth in January 2003. He netted 36 times in 81 Premier League appearances for Pompey before switching to the Riverside in a £7.5m deal two years later.

He continued his fine scoring record there, grabbing 35 goals in 103 outings for the Teessiders in all competitions.