The demand, made on Chirac's return from a three-week vacation in Canada, came as France's main undertakers' group, the Pompes Funebres Generalesannounced that there had been 10,400 more deaths than usual across the country so far this month.

Although the group -- which handles 25 percent of France's funerals -- did not draw a link between the deaths and the heatwave, the government and doctors groups have acknowledged that the final toll was likely to be in the thousands.

French Health Minister Jean-Francois Mattei said Monday that it was "plausible" that the number of deaths linked to the heatwave could be around 5,000, but added that more precise figures would be known in the next few weeks.

His office on Wednesday refused to confirm the undertakers' figures, saying "only a scientific tally... will allow us to know exactly how many deaths were linked to the heatwave."

Patrick Pelloux, the head of an emergency room doctors' union who first raised the alarm over the number of dead, expressed shock at the new numbers.

"If the PFG's figures turn out to be right, this is a humanitarian catastrophe, a major crisis for our country," he said.

The deadly heatwave, which roasted France for the first two weeks of August, claimed mostly elderly victims unable to cope with the 40-degrees-Celsius (104-degrees-Fahrenheit) temperatures.

The PFG said that the Paris region itself had recorded 3,000 more deaths than was typical for this time of year, based on comparisons with the number of August funerals in previous years.

Estimates for the entire month of August suggested more than 13,600 funerals than normal would take place, it added.

Chirac, who refused to cut short his vacation when the scale of the disaster became known, has ordered the ministers concerned to give detailed answers as to how the heatwave and its health consequences were handled.

Accounts were to be given at a regular cabinet meeting to be chaired by Chirac on Thursday, his office said.

Doctors groups and the left-wing opposition have accused the government of failing to act quickly enough to tackle the heatwave crisis even after it became clear that it was claiming a terrible toll, particularly among elderly citizens.

France's surgeon-general Lucien Abenhaim resigned Monday, but told newspapers he was merely a "scapegoat" and suggested his superiors in the health ministry had a share of the responsibility.

Mattei has been singled out for much of the blame but has refused to step down, saying he was only belatedly made aware of the seriousness of the crisis.

TERRA.WIRE