Tal Ben Haim is considering legal action against West Ham United.
The Israel defender claims there was a performance-related clause in his loan contract with the Hammers, which binds the Premier League side to extend his stay there.
A West Ham spokesman dismissed Ben Haim's claims, saying: "As far as the club is concerned Tal Ben Haim is back with Portsmouth and a Portsmouth player."
Ben Haim returned to Fratton Park last week. But Portsmouth, recently out of administration, cannot afford Ben Haim's £37,000 weekly salary.
Steve Cotterill, the Portsmouth manager, said: "As a player we would welcome him. Whether we would welcome his wage is a question for someone else."
Ben Haim's agent Pini Zahavi, who has met Portsmouth's Israeli co-owner Levi Kushnir in Tel Aviv, said: "Ben Haim won't play for Portsmouth again, and we will know quite soon what is going to happen with West Ham."
Regardless of the legal wrangling, Ben Haim's Premier League career - which began in 2004 - appears over for the time being. Even if Ben Haim's claims are valid, West Ham have named their 25-man Premier League squad and Ben Haim is not eligible to play.
Ben Haim turned down a move to Maccabi Haifa saying he wants to stay in England. But it appears that unless there is a change of heart from Portsmouth, Ben Haim could be spending several months on the sidelines.
Dekel Keinan made his debut for Cardiff City in the 1-0 win over against Swansea in the Championship.