Lawyers in France and US may share evidence against Strauss-Kahn

The prospect emerged last night of a transatlantic "merging" of evidence in the separate American and French allegations of attempted rape against the former IMF chief, Dominique Strauss-Kahn.

According to the French newspaper Le Figaro, the New York district attorney, Cyrus Vance, plans to question the 32-year-old French writer, Tristane Banon, who accuses "DSK" of attacking her in a Paris apartment in 2003. Ms Banon's lawyer, David Koubbi, met Mr Vance in New York this week to discuss similarities between Ms Banon's claims and the accusation that the former French finance minister sexually assaulted a chambermaid in a New York hotel in May.

Le Figaro's website, quoting a source close to the New York investigation, suggested that Ms Banon had agreed to speak to Mr Vance and that formal clearance was being sought from the French judicial authorities. It is not clear whether Ms Banon would travel to New York or give her evidence in Paris.

Such a development would suggest that Mr Vance is still making strenuous efforts to prop up the New York case against DSK, who is due to appear in court on 1 August. There was widespread speculation two weeks ago that the case would be dropped after Mr Vance had himself cast doubt on the evidence given by the chambermaid, Nafissatou Diallo.

Ms Banon, the god-daughter of DSK's second wife and a former friend of his daughter Camille, made a formal complaint in Paris earlier this month that the politician had attempted to rape her during an interview for a book in 2003. She said she had decided not to press charges at the time on the advice of her mother, a Socialist Party county councillor in Normandy.

The "affaire Banon" has exploded in France over the last two days into a complex political psychodrama. The former Socialist Party leader, François Hollande – who replaced DSK as the frontrunner in the Socialist primary in October – was questioned yesterday by police investigating Ms Banon's allegations.

Ms Banon said she spoke to Mr Hollande on two occasions soon after the alleged attack in 2003 and that he was supportive and encouraged her to make a formal complaint. Mr Hollande has reacted furiously to what he sees as a "political manipulation" by forces close to President Nicolas Sarkozy, attempting to link him to the "affaire DSK". He was especially infuriated by a front-page story in the Sarkozy-supporting newspaper, Le Figaro, on Tuesday, which placed images of himself and Ms Banon close together.