Sanchez's temporary stewardship at Craven Cottage was today made permanent with the club rewarding his success in keeping them in the top flight with a rolling one-year contract.

The 47-year-old had hoped to combine his two roles but Fulham issued a 'them-or-us' ultimatum that, given his ambition of managing in the Barclays Premiership, left him with no choice.

He leaves Northern Ireland, who top their Euro 2008 qualifying group and sit 33rd in the world rankings, on a high but knew the time was right to move on.

"I am sad that after three and a half years and seeing Northern Ireland to the top of the group it's come to this," he said.

"I had lots of discussions with Fulham and it became evident that I had to concentrate on one job. I can understand that.

"The Premiership is the show because there's a lot of money involved at this level.

"If anything went wrong with one or the other, I'd be blamed for not concentrating on either.

"The compelling reason was you have to give 100% commitment or else you get caught between two stalls.

"I wanted to manage here so I had to make the decision. Northern Ireland would have accepted me doing both roles it but Fulham would be my main employer so it was up to them.

"I was perhaps a little bit naive to think they could be done together but now the decision has been made I'm very pleased to be Fulham manager.

"I have great affection for Northern Ireland and I wish them all the best for the future. Whoever takes over that job will have a fantastic position.

"They are at the top of their group with their highest ranking ever and a Sky TV deal worth £10million.

"The Irish Football Association are disappointed but they understand the situation and they didn't want to stand in my way.

"I always said I wanted to manage at the highest level and league-wise the Premiership is that."

The speed of Sanchez's appointment came as something of a shock to the IFA, who had expected discussions over his future to begin early next week and will now be seeking compensation.

He was contracted to see out Northern Ireland's Euro 2008 qualifying campaign and guide them through the championships itself if they reached that far.

IFA president Jim Boyce told Sky Sports: "Lawrie told me he tried to persuade Fulham he could do both jobs until the end of the European Championships.

"But he was told he either had to resign as Northern Ireland manager or not be considered for the Fulham job.

"It was Fulham's decision, 100%. Lawrie has a contract with the Irish Football Association and he has now broken that.

"We were approached five weeks ago for Lawrie to manage Fulham on a caretaker basis.

"The IFA agreed but were assured that should he be offered the job full-time he would be allowed to manage Northern Ireland through to the end of the European Championship.

"We probably have the best chance of qualifying for a long time and now our manager has been taken away from us."

Sanchez replaced Chris Coleman on a short-term, five-match contract last month but with one game left to go - Sunday's trip to Middlesbrough - he had done enough to convince Fulham he was the right man for the job.

Four points from four games proved enough to guarantee the Cottagers' top flight survival and the former Wimbledon defender vowed he would not preside over another battle against relegation.

"This club is focused and geared towards making sure there isn't another fight at the bottom of the table next year," he said.

"We've had the warning this season and it was a warning for everybody.

"Next year I will be able to refer to what happened this season and say we're going to have that again.

"From now on we move forward because that was a wake-up call. Only when we had the change of manager did the gravity of the situation really sink in."