Ségolène Royal, the Socialist runner-up in last year's French presidential election, drew fire from the Government and her own party today after suggesting that President Sarkozy was behind a burglary at her home.

Intruders ransacked Ms Royal's flat in the western Paris suburb of Boulogne on June 27. They stole nothing but tore up and left on display a police report that Ms Royal made about a break-in at the flat last year.

“I note that a day after I said we needed to end the Sarkozy clan's grip on France, my home was turned upside down," she said on television. "I draw a connection between the two."

Ms Royal's charge was part of a new offensive against the President as she campaigns to become the new Socialist Party leader in autumn.

Mr Sarkozy's governing Union for a Popular Movement said that Ms Royal was losing her nerve. “She has lost control of herself,” said François Fillon, the Prime Minister. “The way she levelled such an insinuation at us without any kind of proof is shameful,” he said.

Last week Mr Fillon accused Ms Royal of “behaving like a little girl throwing a playground tantrum” after she attacked Mr Sarkozy for taking credit for the release of Ingrid Betancourt, the Colombian politician who was held hostage for six years.

Ms Royal's rivals in the bitter campaign for the party leadership lent her little support. Arnaud Montebourg, the young Turk of the would-be leaders, said that break-ins were “a risk that goes with the job” and that all politicians were exposed to them.

Laurent Fabius, a former Prime Minister, who also wants to be leader, said: “Either what she said is accurate, in which case it is clearly scandalous, or it is not accurate in which case she should not say it.”

Ms Royal, who cultivates the image of a Joan-of-Arc-style warrior, has been gunning for Mr Sarkozy for weeks. On Tuesday she said that he had returned France to the days of the pre-revolutionary monarchy, “in which the king entertains himself, he spends the treasury, taking care of his friends, making the rich richer. Money is not important for him because he's loaded with money.”

Since losing the presidency by six points in the run-off vote in May last year, Ms Royal is struggling to rebuild her popularity within the party and the public at large. She is, however, one of the leaders of the field of six would-be party chiefs.

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