The 25-year-old completed the move from Tottenham Hotspur late Monday after passing a medical and agreeing personal terms.

Carrick will earn a reported 50,000 pounds a week, a big boost to his Spurs wage, prompting some commentators to question his motivation for switching clubs again just two years after arriving at Tottenham.

Despite rejecting an improved deal at Spurs, where his contract had two years left to run, the midfielder denied wages were a factor.

"This is a football decision, a decision not driven by money. It's an offer that has come at the right time for me both professionally and personally and I felt I couldn't turn it down," Carrick said.

He was at pains to praise Tottenham, especially manager Martin Jol.

"I've had a great time at Spurs and the club has been brilliant for me. There is an excellent squad full of top players and a number of younger lads coming through the ranks as well. I can only see successful times for the club in the future," Carrick said.

"Martin is a great manager and has done an enormous amount for my career. Without any doubt he has helped develop me into a better player.

"He gave me a chance when I needed it, stood by me and I will always thank him for that."

Jol was similarly effusive about his former charge, saying of Carrick: "He always gave his best and was a wonderful servant. I'm sure he will do well at Manchester United because he is very talented and we will miss having him around."

Carrick, who is due to be formally unveiled at a press conference later this week, is the fifth most expensive signing in Manchester United's history.

Red Devils' boss Sir Alex Ferguson has assigned Carrick the number 16 shirt -- unused since the abrupt departure of midfield legend Roy Keane in November.