Prosecutors will agree to drop the charges against Dominique Strauss-Kahn — either on his next court date in two weeks or even sooner, according to a top investigator in the case who called the eventual dismissal “a certainty.”

“We all know this case is not sustainable,” the source told The Post exclusively yesterday.

“Her credibility is so bad now, we know we cannot sustain a case with her,” the source said, referring to the Guinean hotel maid who accused Strauss-Kahn of trying to rape her in his plush Midtown hotel suite — shocking charges that got the international banker bounced as head of the IMF and also derailed, at least for now, his bid to become president of France.