The Cottagers will allow their Bulgarian striker to rejoin Tottenham but only if they can finalise a move for Olympiakos' prolific striker, although talks are ongoing
Dimitar Berbatov and Lewis Holtby will only be involved in a swap deal if Fulham can finalise a move for striker Kostas Mitroglou.
Fulham are content for Berbatov to leave Craven Cottage in the next 48 hours for a cut-price fee of around £1.5 million, but only if they can secure a replacement forward.
The west Londoners have been in talks with Olympiakos for Mitroglou but they are still working towards an agreement with the Greek club.
Fulham will continue to negotiate for the prolific centre-forward on Thursday as they assess Tottenham's interest in a swap involving Berbatov and Holtby.
Goal understands Spurs chairman Daniel Levy is open to a return for former White Hart Lane favourite Berbatov, but his enthusiasm is not matched by new manager Tim Sherwood.
Negotiations to take the Bulgarian back to north London stalled on Wednesday, which could partly be explained by the frosty relations between Tottenham and Fulham.
Nevertheless, the Cottagers have registered their interest in taking Holtby on loan until the end of the season.
Holtby’s former club Schalke are also interested in re-signing the midfielder, who is a target for the Bundesliga club as they attempt to bolster their team before giving the green light for Julian Draxler to move to Arsenal.
"I'm happy to keep everyone we've got, and if they do move it would be my decision," Spurs manager Tim Sherwood said on Wednesday night.
"[Holtby] comes into that category. I've heard a lot of speculation about him and obviously with the World Cup coming these guys want to play. We won't do anything that isn't right for the club."
Berbatov is settled in London and has privately ruled out a switch to anywhere outside of the capital. However, it is believed that neither Arsenal manager Arsene Wenger or Chelsea boss Jose Mourinho are interested in the Bulgarian, who turns 33 on Thursday, despite their stated need for fresh blood up front.
Tottenham are looking for a replacement for Toronto-bound Jermain Defoe, who will make his White Hart Lane exit on February 28, leaving Sherwood with just two senior strikers in Emmanuel Adebayor and Roberto Soldado.
Levy was angered at the manner in which Berbatov engineered his £30.75m exit to Manchester United in 2008 but tried to re-sign the striker on deadline day in August 2012 before he committed to Fulham.
Berbatov has not been quite as effective in his second season at Fulham and the west Londoners are keen to sign a more mobile front man.
They have been negotiating for Mitroglou but are unwilling to pay €13m for the 25-year-old, who has scored 23 goals in 25 matches for club and country this season.
Meanwhile, Fulham will allow Adel Taarabt to join AC Milan on loan before the window closes. The playmaker is on loan from QPR but is surplus to requirements at Craven Cottage and a deal has been agreed for him to move to the San Siro.
Taarabt is set to undergo a medical with Milan on Thursday, freeing up a loan space in the Fulham squad for Holtby.