The French rugby federation on Thursday reported another player had tested positive for coronavirus ahead of their Six Nations match against Scotland this weekend, and cancelled the day's training.

Sunday's game at the Stade de France was placed in doubt after 15 France players and staff previously contracted the virus, but tournament organisers had announced on Wednesday the match would go ahead.

But that decision was made after no new cases were found in Monday and Tuesday's tests, with the entire France group now in isolation just three days before the fixture.

"Following the RT-PCR tests carried out this Wednesday, February 24 in the evening and the appearance of a positive case within the squad of players, the FFR medical committee met this morning and decided to suspend training today," the FFR said in a statement.

The FFR did not identify the latest player to test positive, but captain Charles Ollivon, star scrum-half Antoine Dupont and coach Fabien Galthie were all among those to contract the virus following their February 14 win over Ireland in Dublin.

"The entire group is in isolation in accordance with health protocol. The FFR is in close contact with the Six Nations committee," the FFR added.

Apart from Ollivon and Dupont, France will also be without backs Arthur Vincent, Gabin Villiere and Brice Dulin as well as the entire front row of Cyril Baille, Julien Marchand and Mohamed Haouas.

The Six Nations match between France and Scotland on Sunday is in doubt again
The Six Nations match between France and Scotland on Sunday is in doubt again AFP / FRANCK FIFE

Scotland were eager to play the game as scheduled, with a postponement to next week potentially seeing 10 away players miss out due to their commitments with non-Scottish clubs.

"We made our case quite clear to the Six Nations about why we wanted the game played this Sunday and we look forward to a great contest," said Scottish Rugby Union chief executive Mark Dodson on Wednesday.

"Touch wood, we're ready to go this Sunday."

On Wednesday, French sports minister Roxana Maracineanu also demanded FFR president Bernard Laporte launch an investigation into the outbreak.

The minister asked health officials to examine "how the chain of contaminations was formed" within the squad.

Les Bleus, bidding to win the Six Nations title for the first time since 2010, are sitting top of the table after beating Italy and Ireland in their opening two games.

Galthie's side are ahead of second-placed Wales, the only other team with a chance of completing the Grand Slam, on points difference.