Resurgent conspiracy theories over the Dominique Strauss-Kahn sex assault case angered the French government on Monday, as speculation rose that he may return to the presidential race if cleared.

Former International Monetary Fund (IMF) chief Dominique Strauss-Kahn and his wife Anne Sinclair leave their temporary Manhattan residence in New York July 2, 2011. [Photo/Agencies]

Interior Minister Claude Gueant denounced as "odious" the insinuations by two of Strauss-Kahn's allies in the Socialist Party, Paris Regional Councilor Michele Sebban and MP Francois Loncle.

Sebban had branded the arrest "a political assassination", hinting that the management of the hotel in which the alleged assault took place - the Sofitel, part of the French group Accor - was complicit.

She also cited reports in US media of cozy ties between President Nicolas Sarkozy and New York police chief Ray Kelly.

"What they are saying is truly scandalous," Gueant said on France 2 television on Monday, confirming that he was informed of the arrest a few hours after it happened by the presidential intelligence chief.

"If Mr Loncle has accusations to bring he should take judicial action or shut up. These accusations are odious," he added. "It is out of the question that anyone in France could manipulate American justice."

A source close to the case who asked not to be named said that the management of the Sofitel New York informed Accor of Strauss-Kahn's arrest within an hour of it happening, and Accor then told the French presidency.

"The question of timing is important. It is relevant to know when the Accor group was informed and when Claude Gueant was informed," Loncle said on Sunday.

The French intelligence service DCRI said it had no role in the affair. Accor in a statement denied that any of its managers were involved and warned the claims could be "defamatory".

The presidential palace declined to comment.

"I prefer to think of it as a trap rather than a conspiracy," said Pierre Moscovici, a senior Socialist Party member and ally of Strauss-Kahn.

"Once it is known that, as I believe, there has been a judicial mistake, we will search carefully to know what happened and how this trap was set," he said on BFMTV television.

Strauss-Kahn, who was head of the International Monetary Fund and favorite to beat Sarkozy in next year's election until the scandal hit, walked free from house arrest on Friday pending his next court appearance.

Prosecutors had admitted to doubts over the credibility of the Guinean hotel maid who accuses him of trying to rape her, saying she was suspected of lying to police.

Socialist Party leader Martine Aubry said on Sunday "no one would dare" oppose the return of Strauss-Kahn if he is cleared and decides to re-enter the presidential race.

Jerome Fourquet, head of the IFOP polling institute, told Le Figaro newspaper that obstacles remained for Strauss-Kahn even if he makes a dramatic comeback from the humiliation of the sex charges.

"He would have the image of someone who has been unjustly dragged through the mud. That could move even people who do not share his political views," he said.

"On the other hand, when it comes to money and his lifestyle, it is more problematic, particularly for a left-wing candidate," he added.

Opponents have branded Strauss-Kahn a "champagne socialist" and for them this image was reinforced, said Fouquet, when he was seen dining in style in New York after his release from house arrest.

"We have seen that DSK has financial means far removed from those of ordinary French people," Fouquet said. "If he comes back to politics, he will be judged on his lifestyle."