Hull manager Phil Brown admits he may have to pursue other targets if a deal cannot be concluded for Marc-Antoine Fortune in the next two days.
The Nancy striker has agreed terms with the Tigers and the clubs have settled on a fee but the player is yet to commit.
Brown said: "It hasn't moved forward in the last 48 hours. He has an offer from us and an offer from Celtic and someone has said something about West Ham."
He continued: "That is news to us but if so, so be it. We are now in a three-horse race as opposed to a two-horse race.
"We are confident we are still in the pole position but these things are always a concern when they are not done and dusted.
"If there is not a decision in the next 24 or 48 hours we are going to have to move on to other players."
Hull are also hoping to secure a club-record deal for Manchester United forward Fraizer Campbell following his return from the European Under-21 Championship in Sweden.
Campbell, a favourite at all Hull after a successful loan in 2007-08, has also been linked with Sunderland.
Brown added: "We have been in constant contact with Manchester United, Fraizer and his father, and hopefully we can now sit down and draft a deal before he goes on his family holiday."
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