The president of Castres says they are travelling to Limerick to play Munster against their wishes.
Saturday's Pool B game is the only Heineken Champions Cup fixture this weekend involving a French side still set to go ahead.
Leinster's game away to Montpellier was awarded a 28-0 bonus point win for the Top 14 team, after an EPCR Match Risk Assessment Committee decided that Leo Cullen's side could not fulfil the fixture.
On Friday, European rugby bosses decided to postpone all matches this weekend which were to pit French teams against sides from the UK.
That decision left Castres as the last French team standing this weekend in the Champions Cup.
Their president, Pierre-Yves Revol, told the club's website that the Top 14 clubs were "unanimous" in requesting all remaining pool games be cancelled.
According to Revol, they wanted to see the tournament played on a knockout basis avoiding two-way trips.
He claims English Premiership and United Rugby Championship clubs pressured the EPCR in maintaining the current format of the competition.
Revol added, "The postponement of the whole round of fixtures would have been more logical, understandable and clear.
"I would add that in terms of health, the situation in Ireland today does not really differ from that in Great Britain."
Revol told his club's website that the financial implications involved in not fulfilling the Munster game were too great to consider.
The Castres president says they were given assurances regarding Munster's squad health - especially after their ill-fated trip to South Africa.
According to Revol, some players were not considered for the Limerick trip to preserve them for festive Top 14 action. They currently sit 6th in the table, a point behind Ronan O'Gara's La Rochelle.
And while he regards a game at Thomond Park as a "great adventure for a player", Revol described it as absurd that they're the French team in action this weekend.
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