Tal Ben-Haim is unlikely to return to Pompey.
The Israeli defender has been on loan at West Ham since August and is in negotiations over extending his stay at Upton Park.
Although Pompey are desperately short of players, with injuries and suspensions affecting Steve Cotterill's squad, Ben-Haim's wages are believed to be way beyond what the club can afford under their budget restrictions.
But negotiations are at a delicate stage for the versatile defender, who joined Pompey in August 2009.
It remains unclear whether a permanent transfer or loan extension is being discussed, and Blues chief executive David Lampitt was understandably reluctant to go into details.
He said: 'Discussions are ongoing regarding Tal Ben-Haim.
'There have been talks between the clubs, the player and his representatives.
'We're working with West Ham and have been in contact with them frequently.
'Hopefully, there will be a resolution in the near future but it's difficult to go into details at this stage.'
Although it remains unclear who is currently paying the wages of the 28-year-old, it seems to be in the best interests of all parties that a deal can be agreed.
But a potential stumbling block could be the ongoing speculation surrounding the future of former Blues boss Avram Grant, who has come under increasing pressure and was widely expected to be sacked last weekend.
Grant recently insisted he was keen to keep the player.
He said: 'We very much want Tal to stay. We have a problem over his contract with Portsmouth but he is good for us, and if they agree, we want to loan him until the end of the season.'