Particular venom was reserved for Elisabeth Guigou

At the time, Ms Guigou was European affairs minister under President Francois Mitterrand and Mr Vedrine was secretary-general at the Elysee palace.

According to Dumas, Mr Mitterrand and all his entourage knew of a payment of 256 million francs which went in 1992 to oil Elf's purchase of the eastern German oil refinery Leuna - money which it is alleged went to the CDU party of Mitterrand's close ally, Helmut Kohl.

The same charge was made last week in the German weekly Der Spiegel by Elf's boss at the time, Loik Le Floch-Prigent - also convicted in the Paris trial.

Venom

"When Le Floch says he went to consult the president and that everyone around him at the Elysee knew of the affair - Madame Guigou, Monsieur Vedrine - he has to be telling the truth," Dumas said.

His particular venom was reserved for Ms Guigou, who as justice minister till last year, ultimately presided over the investigation that led to his conviction. "If you want to say that I am paying for Madame Guigou, then I won't deny it," he said.

If it were established that Ms Guigou and Mr Vedrine did indeed know of the commissions then their positions would be severely compromised

"It is nothing personal, but she was minister of justice throughout all this period, and I think that she has not always contributed to the smooth functioning of justice."

It all amounts to the clearest sign yet that the scandal at Elf - what Dumas referred to as France's milch-cow - has plenty more secrets to be uncovered. Did not the key figure in the affair, Alfred Sirven - the man who ran the slush fund - once say he knew enough to bring down the republic 20 times over?

If it were established that Ms Guigou and Mr Vedrine did indeed know of the commissions - they immediately denied the allegation - then their positions would be severely compromised.

As Dumas said: "There is a desire to protect those who are still in charge. A lot of people do not want the truth to come out. This issue will be very alive in the coming weeks."

Watchful Jospin

There is no certainty of the affair developing into an all-out government crisis.

In Britain or America, ministers facing this level of accusation would be under intense public grilling from newspapers and broadcasters demanding an explanation.

But in France, tolerance of top-level corruption is higher and the press far less inclined to mount a campaign do de-throne the country's leaders.

The glacial slowness of the judicial system doesn't help either.

All that can be said for certain is that Prime Minister Lionel Jospin - already under pressure over the revelations about his Trotskyist past - will be watching events with some apprehension.

He deliberately marked his distance from the Mitterrand era when he became prime minister in 1997 - precisely because of its reputation for loose ethics.

But the late president cast a long shadow. Many secrets remain to be told.