VITESSE Arnhem have revealed the transfer of Alexander Büttner to Saints is now "uncertain".
The Dutch side have blamed demands made by a "third party" which they say they will not be pressurised into accepting.
Vitesse have confirmed that Saints have acted "absolutely correctly" in their approach to the deal and are not to blame if it falls through.
A statement from the club said: "The transfer of Alexander Büttner to Southampton FC is now uncertain.
"Last Friday Vitesse came to an agreement with Southampton about the transfer of Alexander Büttner to the Premier League club.
"Because Büttner himself also agreed on his personal conditions with Southampton FC, Vitesse was in the supposition that the transfer was a fact, with the proviso that Büttner would pass a medical examination.
"However, in the course this weekend the player informed Vitesse via his agent that a third party had a supplementary demand towards the club.
"Vitesse gave to understand to the player that it would not comply with that demand, since it was applied in retrospect and Vitesse will not be pressurised.
"Vitesse is disappointed about the course of things, all the more because Vitesse negotiated with Southampton FC on the player's request.
"Southampton FC has taken up an absolute correct position and is not to blame for the possible fall through of the transfer. Vitesse have also tried all possible to keep the set deal going."
