Portsmouth manager Harry Redknapp is poised to drop his interest in Bulgaria captain Stilian Petrov after Celtic rejected his latest £5m offer.
Petrov is under contract at Celtic until 2010
The midfielder wants a move to the Premiership, but Celtic have so far refused his transfer request.
"As far as I'm aware, Celtic have turned down our £5m and I think that's it over," Redknapp told The Sun.
"I have a high regard for Petrov's talent and I'd have been delighted to have signed him, but enough is enough."
Some reports suggest Portsmouth will now shift their focus to Real Madrid's Thomas Gravesen, who has himself been linked with Celtic.
"I couldn't honestly recommend to the club to pay any more for the boy," said Redknapp.
"I believe we were the only club in for Petrov and I reckon Celtic might find it difficult getting better money than that."
Petrov is under contract until 2010 but has made public his desire to play in England's top flight.