The Chiracs' lavish lifestyle at the Paris town hall will be scrutinised

Paris investigating magistrate Philippe Courroye ruled last week that he would open a preliminary investigation despite a recommendation from prosecutors to drop the charge, the sources said.

The move comes after the incumbent Paris mayor, Socialist Bertrand Delanoe, filed a civil complaint last year on Mr Chirac's huge food bills.

The affair was dubbed Applegate after journalists worked out that the Chiracs' grocery bill meant they could have afforded 100 kilos (220 lb) of apples a day.

Mr Chirac remains immune from questioning or possible prosecution as long as he is head of state, but his wife Bernadette is not covered by the immunity.

Mr Delanoe filed the complaint after an audit he ordered found Mr Chirac and his wife spent 2.2 million euros on wine and food for private receptions between 1987 and 1995, more than half of it in cash.

The audit said that out of that sum, some 1.4 million euros were given in cash to the mayor's personal cooks, without any control.

The audit pointed to some bills which appeared to have been paid several times, and others which appeared to be for fictitious items.

Judge Courroye agreed with the prosecutors' recommendation earlier this year that a possible charge of embezzlement should be dropped because the deadline by which the charges should have been prosecuted had passed.

But the Paris judge said the charge of alleged false billing should be investigated.