Traoré, who was snapped up by the Ligue 1 title challengers at the weekend, will attend a London hearing to discover his fate but it is unsure at this stage whether he will travel to London to complete his medical ahead of his scheduled move to the Hammers.
According to the report, the 6ft8 frontman was pencilled in for the customary check-up at the east London club's Chadwell Heath training ground tomorrow but it is now unclear whether this will take place as originally planned.
Sam Allardyce has been hoping to tie up the Ivorian's signature in time for this weekend's trip to Cardiff City, but the Hammers chief must continue with a striker shortage until next week, with the former Bolton manager also hopeful of adding Inter Milan forward Ishak Belfodil to his ranks.
The report adds that, while a deal between the two clubs for Traoré is complete, there are now tangible doubts over the striker's eligibility for a permit to secure his switch to the Premier League.
The Hammers have won just two of their last 13 matches in all competitions and the need for striking reinforcements was highlighted after an embarrassing 5-0 FA Cup humbling at Nottingham Forest.
image: © Tom Cuppens