West Ham's delay in tying Winston Reid to a new contract is "probably down to money", according to manager Sam Allardyce.
The New Zealand defender is in the final year of his current deal at Upton Park but has yet to put pen to paper on an extension, with reports linking him to a host of leading Premier League clubs.
Allardyce has reiterated his desire to see Reid remain in east London, but says negotiations are now in the hands of chairmen David Gold and David Sullivan.
"It's an ongoing negotiation at the moment," he said. "We want him to stay at the club, he's a great player who has done fantastically well for us.
"The chairmen will notify whenever an outcome, either way, has been reached.
"Like everything these days, it's probably down to money."
Reid has established himself as a key player with West Ham since his move from Danish side FC Midtjylland back in 2010.comments