French club Nantes have reportedly demanded the transfer payment from Cardiff City for Emiliano Sala who is missing, assumed dead, after a plane he was in went missing over the English Channel.
Cardiff City had agreed to a club record £15 million to sign the striker from the French club.
According to the BBC, Nantes are threatening legal action if they do not receive a payment within 10 days.
A source at Cardiff City told the BBC that they were prepared to pay Nantes the fee once they had "all the facts" but were surprised the French club was making demands at the point of time.
Authorities said yesterday they are trying to recover the body spotted in the seabed wreckage of the plane that was carrying Argentine player and his pilot.
The aircraft disappeared over the English Channel on January 21as it flew from the French city of Nantes to Cardiff, where Sala was due to start playing in the Premier League.