Fallen French politician Dominique Strauss-Kahn could be freed this week, as prosecutors reportedly prepare to dismiss explosive charges that the former IMF chief sexually assaulted a hotel maid.

‘The New York Post’, citing sources close to the prosecutors, said Manhattan District Attorney Cyrus Vance has concluded that the charges cannot be proven beyond a reasonable doubt and will ask a New York judge to dismiss them at a hearing on Tuesday.

Nafissatou Diallo, who accused Strauss-Kahn of forcing her into oral sex and trying to rape her when she came to clean his luxury hotel room on May 14, has been summoned to a meeting on Monday with prosecutors.

Kenneth Thompson, who represents the 32-year-old Guinean immigrant, said after receiving Vance's letter that he thought all or some of the charges against Strauss-Kahn could be dropped.

"My interpretation of that letter is that they're going to announce that they're dismissing the case entirely, or some of the charges," Thompson told ‘The New York Times’ on Saturday.

"If they were not going to dismiss the charges," he added, "there would be no need to meet with her. They would just go to court the next day to say, 'We're going to proceed with the case.'"

Another attorney for Diallo, Douglas Wigdor, described the letter from prosecutors as "very negative and disparaging."

The terse letter from assistant district attorney Artie McConnell says Diallo has been invited "for the purpose of my explaining to her what I anticipate will occur in court" on Tuesday.

"Due to a variety of circumstances, I am advising you in advance that I will not be able to alter the time and date of this appointment," the letter says.

Prosecutors refused to comment when contacted by AFP about the Post report.

Strauss-Kahn, 62, who quit as head of the International Monetary Fund after his arrest, has pleaded not guilty and is free on bail.

His attorneys have said the charges should be dropped so he can return to France, where until recently he was seen as a frontrunner for the presidency.

Tuesday's hearing in New York state court will be the first since prosecutors announced they had serious doubts about Diallo's credibility.

The Post said that in his motion to dismiss, Vance will review the findings of his four-month investigation, including previously undisclosed information, that put her credibility in question.

The first blow to prosecutors was the revelation that Diallo lied to immigration officials on her asylum application about a gang rape she said took place in her West African homeland.

That was seen as making her an easy target for Strauss-Kahn's attorneys when she took the stand in a trial that would in large part come down to her word against that of Strauss-Kahn.

On Friday, reports in The Wall Street Journal and the online Daily Beast quoted unnamed sources saying that Thompson had negotiated weeks ago with Strauss-Kahn's side about dropping the charges in exchange for a cash payoff.

Amid a slew of negative media coverage about Diallo -- including so-far unproven allegations that she discussed with a friend the possibility of making money from Strauss-Kahn -- she and Thompson launched a media blitz in late July.

The offensive, including print and TV interviews with Diallo and a press conference at a big African American church in New York, helped to rehabilitate her public image.

However, it is very unusual for complainants in sex crime cases to go public and legal experts say that Diallo's multiple statements regarding her allegations could make her even more vulnerable on the witness stand.

In a further indication that her lawyer thinks the criminal trial will not take place, Diallo filed a civil suit seeking damages against Strauss-Kahn.

Unless there is a postponement, two main options remain for Tuesday: prosecutors telling the judge they plan to go ahead with the case, or prosecutors moving to dismiss charges.

"The DA's office will do whatever's in the future political interests of Cy Vance," said prominent defense lawyer Ron Kuby. "They certainly haven't done a great job so far."

The prosecution case is not necessarily irreparable, but the odds now favor Strauss-Kahn, Kuby added.

"The defense has done remarkably little and they've done it brilliantly," he said.