The England under-20 international has handed in a transfer request to the club with less than two weeks left until the end of the transfer window.

West Ham United have been linked with Halford, 21, but the U's say they have received no offers so far.

"We're not looking for Greg to leave. There is a valuation to be met before we even consider letting him go," boss Geraint Williams told BBC Essex.

Colchester United chief executive Marie Partner spoke of her disappointment at Halford's transfer request.

The oldest trick in the book is to unsettle a player Marie Partner Colchester United chief executive

"We're not surprised. There's been speculation and approaches from clubs for the last year or so," she said.

"It hasn't come at the best of times as we're trying to bring players in, not lose them.

"We haven't actually sat down and spoken to the lad about what he wants to do. Without doubt outside influences have got to him.

"The oldest trick in the book is to unsettle a player and with the transfer window closing this puts us under massive pressure," concluded Mrs Partner.