But the midfielder claimed Hammers manager Harry Redknapp had begged him to stay at Upton Park.

Impey signed a three and a half year contract with the Filbert Street side after protracted negotiations between the two clubs were settled on Tuesday.

Redknapp had criticised the West Ham board on Sunday, accusing them of agreeing to sell Impey behind his back.

But Impey admitted the writing was on the wall for him at Upton Park after he learnt that a deal had been agreed by the Hammers with Leicester manager Martin O'Neill.

Redknapp launched a fierce verbal attack on his board

Impey said: "There has been a lot of talk about the manager (Harry Redknapp) not being happy, and I think the matter was taken out of his hands a bit.

"I had said to him that when everyone at West Ham was fit, I didn't think I would be in the team. He assured me I would be and begged me to stay.

"But when a club does a deal with somebody else and agrees terms, I think the writing is on the wall.

"If they were prepared to sell me, then I was prepared to go, although it came as a bit of a shock to me.

"The manager said he wanted me to play at Derby on Sunday, but then I found out I was being left out late on Saturday."

O'Neill said: "I was interested in signing him a year ago when he was transferred from QPR, but I never saw it through.

"He came back available two weeks ago, and that, plus the fact I had only 14 fit players to pick from on Friday, helped to make up my mind, and I think I've got a good player at a decent price.