UNITED NATIONS — One of Colonel Gadhafi’s former diplomats, an envoy who as recently as last year served as president of the General Assembly, has broken with the regime, according to a diplomatic source, and is expected to make an announcement tomorrow in yet another setback for Libya’s strongman.

The announcement expected tomorrow — that Ali Treki, who has served as the president of the General Assembly in 2010, has broken up with the regime — would come on the heals defection earlier today in the United Kingdom of the Libyan foreign minister, Musa Koussa. He went over to Britain’s side only hours after he had named another former Assembly president, Nicaragua’s former foreign minister no less, as Tripoli’s next ambassador here.

These developments are astonishing the diplomats here, where they are seen as a sign that the diplomatic street, so to speak, is discounting Mr. Gadhafi’s chances of hanging onto power in the long term. Mr. Treki, who was Tripoli’s first choice as U.N. ambassador, sent a letter today to Gadhafi, saying he no longer wants to represent the current regime. A diplomatic source added that Mr. Treki, who is currently at Cairo, planned to make his defection public tomorrow.

The rollercoaster-like deluge of events started this morning, when Mr. Koussa sent Secretary General Ban a letter naming Miguel d’Escoto Brockman of Nicaragua as Libya’s new permanent representative to the U.N. Mr. D’Escoto, an old Sandinista hand whose behavior as General Assembly president in 2009 earned him the scorn of numerous diplomats here, initially scheduled a press conference for Thursday morning at Turtle Bay. The event was booked by the Nicaraguan mission to address “the situation in Libya,” according to a U.N. press release.

The American envoy here, Ambassador Rice, publicly wondered this afternoon why the U.N. has allowed Mr. d’Escoto, who “represents seemingly nobody,” to conduct the press conference at Turtle Bay. She noted that Mr. d’Escoto no longer serves as the Assembly’s president and is not a member of Nicaragua’s U.N. mission either. Several minutes after her public statement, the U.N. spokesman sent reporters a revised schedule of Thursday’s press conferences, in which the 10 a.m. session was conspicuously missing. 

   

Although he was born at California, Mr. d’Escoto, a defrocked Catholic priest, renounced his American citizenship several years ago and has been here on a tourist visa, Ms. Rice said. To regain his diplomatic status, she said that he “needs to leave the United States, and apply” for entry as a foreign diplomat and that in such a case his “visa status would be reviewed.”

If Mr. d’Escoto indeed passes all those hoops – a big if – he would become the head of the Libyan mission here, replacing the current ambassador, Mohamed Shalgham, and his deputy, Ibrahim Dabbashi. Both diplomats have sided with the Benghazi rebels early on in the battle for Libya. Their heart-wrenching calls for help at the Security Council, where they detailed Gadhafi’s atrocities, were instrumental gaining passage of the two resolutions that serve as basis for the NATO military operation there. Messrs. Shalgham and Dabbashi are currently allowed entry to Turtle Bay with “courtesy passes,” according to U.N. officials.  Mr. d’Escoto, who during his Assembly presidency used colorful language to denounce Presidents Reagan and George W. Bush, was criticized to reporters today by Mr. Shalgham, while several diplomats here were at a loss yesterday to react to Gadhafi’s latest move.