Welsh side Scarlets had confirmed one of their players which had been in the side that beat Bath last weekend had tested positive for Coronavirus.
Bath’s scheduled game with La Rochelle on Saturday was cancelled after 12 of their squad were deemed close contacts with the Scarlets player and were forced to isolate.
European Rugby had said the Scarlets could still face Toulon after they withdrew the player.
But the French side refused to both take to the field and the offer of delaying the game over concerns the health of their players would be compromised.
A Toulon statement read: “Rugby Club Toulonnais learned this Thursday, 17 December that at least one player from the Scarlets team had tested positive, earlier this week, for Covid-19.
“Following this, the Bath Rugby club, which had faced the Scarlets last weekend, were forced to forfeit the second day of the Champions Cup because 12 players in their squad had been in ‘close contact’ with this Welsh player.
“Despite this eminently delicate context, the EPCR, with the approval of the Welsh Rugby Federation, wished to maintain the Scarlets / Toulon match.
“President Bernard Lemaitre spoke extensively with EPCR Director General Vincent Gaillard.
“He specified that the sanitary conditions were not met to maintain the organization of this meeting the health of the players of the staff and their families being paramount.
“EPCR nevertheless upheld its decision.
“Faced with this state of affairs, the Rugby Club Toulonnais, although aware of the serious consequences, decided not to play this meeting as planned this evening.”
A EPCR statement read: “Following confirmation by Scarlets that one of their players tested positive for COVID-19 after last weekend’s Round 1 match against Bath Rugby, the player self-isolated in accordance with public health guidelines and his two close contacts were not selected in the matchday squad for the Pool A fixture against RC Toulon.
“A Medical Risk Assessment Committee was convened earlier today to consider any potential issues in relation to Scarlets’ testing and tracing, and it was satisfied that the risk of further transmission had been contained before recommending that the match could go ahead safely.
“On learning of RC Toulon’s concerns regarding the fixture, it was suggested that the match could be postponed to a later date in the weekend to allow any of the club’s players to opt out of the match if they wished to do so.
“It was also suggested that RC Toulon could source willing players from their existing tournament squad to replace those who had withdrawn and that the Scarlets matchday squad could undergo additional PCR testing.
“These offers were rejected by RC Toulon, and EPCR can therefore confirm that the match is postponed.”