Heineken Cup chief Jean-Pierre Lux has painted a grim picture of reality for the tournament's future as European rugby's major competition faces meltdown.
French clubs are expected to confirm a boycott of the blue riband tournament next season after their umbrella organisation - the Ligue Nationale de Rugby - stages a board meeting in Paris on Thursday.
Premier Rugby, LNR's English equivalent, has already confirmed it will follow suit if the French withdraw.
Such a doomsday scenario would effectively sound the death knell for any 2007/08 Heineken Cup, leaving Celtic teams reeling from its acute financial fallout and the sport once again in a chronic state of disarray.
The main problem revolves around Premier Rugby's issue with the Rugby Football Union regarding shareholding on European Rugby Cup Limited.
English and French clubs believe an agreement had been reached to resolve the matter last October, but the RFU disputes this, which has prompted a powerful Anglo-French alliance.
However, fixture congestion in France caused by next season's World Cup - and a perceived undermining of the Top 14 French league - is thought to be the real reason behind French clubs' militant stance.
Although the RFU has no doubt top English clubs are contracted to play in Europe until 2009, legal action is unlikely in the event of a withdrawal.
But lawyers can expect to become involved if the clubs make moves to organise Anglo-French fixtures not sanctioned by the RFU and International Rugby Board next term.
In the meantime, ERC must be braced for existing tournament broadcasters and sponsors pulling out, given the tournament's meaningless nature if English and French clubs do not participate.
ERC president Lux said: 'It is a real shame from a sporting point of view that we cannot come to an agreement.
'They (television companies and sponsors) are all calling. They are very worried, and that is normal.
'I am the first port of call for the complaints of Heineken and other partners, who have all the departure clauses in their contracts.
'One week there is hope, the next despair. How can we look for new partners in these conditions? For sure, their confidence in us will be different now.'
The possibility of a French u-turn is remote, although Premier Rugby has said it is committed to exploring all possible solutions over the next few weeks.
'The English have taken the precaution of saying that if the French return, they will play,' Lux told L'Equipe.
'Now, it will be very difficult to prepare for next season if the French and English clubs return. But it will be easier than if we have to go looking for new clubs and invent a new formula, even if it is our job to do that.
'I am not being fatalist, but there are things you cannot control.
'At the end of February, we thought the English were near to an agreement, and then no. Take into account that we began a re-negotiation of (European Rugby Cup) agreements in Paris 15 or 16 months ago.
'If we began two months ago, we would be at the same point.'
RFU management board chairman Martyn Thomas added: 'I hope that PRL and the French clubs consider the other participating Unions in the Heineken Cup, their fans and players who, like us, would obviously want their participation in next year's tournament.
'An important consideration to PRL in reaching this decision will be money. The loss of revenue to PRL for their non-participation in the Heineken Cup will be theirs to absorb alone because the English income from the Heineken Cup is transferred, in its entirety, to the clubs by the RFU.'
