The Libyan leader Muammar Qaddafi received a double blow overnight Wednesday, with the defection of Foreign Minister Moussa Koussa – one of his closest confidants – and news reports that CIA operatives were now working alongside antigovernment rebels in eastern Libya.

Few officials know as much about the inner workings of the Libyan regime as Mr. Koussa, who was Colonel Qaddafi’s intelligence chief for 15 years and liaised with the CIA during the destruction of Libya’s weapons of mass destruction programs and Libya’s subsequent embrace by the West.

Analysts say Koussa’s defection to Britain yesterday – coupled with reports on Al Jazeera English that four more senior Libyan officials are already in neighboring Tunisia, ready to defect – is likely to sow doubt in Qaddafi’s inner circle, despite their recent military gains.

“Moussa Koussa was the closest ally of Qaddafi. He was not just the architect of his foreign policy, he was the architect of his security operations, in particular overseas,” says Fawaz Gerges, director of the Middle East Centre at the London School of Economics (LSE). “If there is one person who knows all the dirty tricks of the Qaddafi regime, it is Koussa. That’s why Koussa’s defection represents a hard blow to Qaddafi himself; he’s an integral part of the Qaddafi inner circle.”

The Libyan government, however, dismissed Koussa’s departure as insignificant. “We are not relying on individuals to lead this struggle,” said spokesman Mussa Ibrahim on Thursday.

“This is the struggle of a whole nation. It is not dependent on individuals or officials,” no matter how high-ranking they may be, said Mr. Ibrahim. “We have millions of people leading this struggle. And this is a fact. So if anyone feels tired, feels sick or exhausted, and they want to take a rest – it happens.”

A two-pronged war

On the battlefield, Qaddafi loyalists in two days have pushed rebels back some 150 miles – all the way to Ajdabiya. Pro-regime forces reportedly mined the road to prevent a repeat rebel advance like the one that raised rebel hopes earlier this week.

It was not clear how much the CIA effort – which reportedly includes small teams tasked with airstrike targeting, and gauging rebel military needs, alongside British special forces – could help the manifestly disorganized, poorly equipped, and inexperienced rebels.

“The alliance is really waging a two-pronged war, with a political and diplomatic campaign in addition to the airstrikes, and Koussa’s defection – along with the expulsion of the five Libyan diplomats [from London] yesterday – signals the first shots in [that] war,” says Gerges in London. “They want to send an unambiguous signal to the people around Qaddafi that the game is over and that time is running out on them.”

A statement released late Wednesday by the British Foreign Office did not use the word “defection,” when it described Koussa arriving at the small Farnborough Airport just outside London “under his own free will,” and declaring only that he was “resigning his post.” But it clearly supported the move.

“We encourage those around Qaddafi to abandon him and embrace a better future for Libya that allows political transition and real reform,” the Foreign Office said.

However, British Foreign Secretary William Hague said on Thursday that Koussa was “not being offered immunity from prosecution” in British or international courts. As Libya’s top diplomat in Britain in 1980, Koussa was expelled for stating that he would eliminate Libyan dissidents living in the country; some reports also link him to planning the destruction of Pan Am Flight 103 over Lockerbie, Scotland, in 1988.

Debate over whether to arm rebels

News of the defection came as reports emerged that President Obama had signed a presidential finding authorizing covert operations in Libya. Reports first emerged in The New York Times that CIA operatives had been deployed to the rebel side in eastern Libya.

That development comes as Washington debates the possibility of providing arms and other fighting expertise to the rebels. The United Nations Security Council resolution approved on March 18 authorizes “all necessary means” to protect civilians, but also rules out foreign military forces on Libyan soil.

The government in Tripoli has cried foul, saying the US, Britain, France, and other Western nations are exploiting the UN vote to engineer the ouster of Qaddafi.

NATO chief Anders Fogh Rasmussen – whose US-led alliance assumed command of all air operations on Thursday – said that the UN mandate does not extend to tipping the military balance with new weaponry.

“We are there to protect the Libyan people, not to arm the people,” Mr. Rasmussen said in Stockholm.

Rebel setbacks in recent days, however, have shown that the ragtag force is not likely to prevail militarily against Qaddafi loyalists without substantial outside help.

“We are seeking weapons that will be able to destroy the heavy weapons they are using against us such as tanks and artillery,” said rebel spokesman Col. Ahmad Bani, according to Reuters. A headlong rebel advance days ago made it to within a few dozen miles of Sirte, Qaddafi’s well-defended coastal hometown, on the back of US- and French-led airstrikes that decimated loyalist armor along the way.

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But the rebels were pushed back as quickly as they advanced, fleeing in panic before the superior firepower of units loyal to Qaddafi.

“We thought it better to make a tactical withdrawal until we can think of better tactics and a strategy to face this force,” said Col. Bani.

West is 'tightening the noose' around Qaddafi's men

After days of military news, and weeks of defiance by Qaddafi – who has said the rebels are drug-addled Al Qaeda militants, “rats” whom he vowed to hunt down “house to house, closet to closet” – the diplomatic impact of Koussa’s departure to Britain took center stage.

“His resignation shows that Qaddafi’s regime, which has already seen significant defections to the opposition, is fragmented, under pressure, and crumbling from within,” said Mr. Hague, the foreign secretary.

Another senior Libyan official who previously defected, immigration minister Ali Errishi, told France 24 television on Thursday that Koussa’s defection was a “sign that the regime’s days are numbered. It is the end … it is a blow to the regime [and] others will follow,” according to Agence France-Presse.

“Koussa is so important because you could not get a bigger fish,” says Gerges of LSE. “The fact that the West is willing to tolerate this man, who has blood on his hands, sends signals to other nasty characters around the Libyan regime that they still have a way out.”

"The meaning of his defection is that the Western-led alliance – including the United States – is trying to really tighten the noose around Qaddafi’s men," he adds. "It’s not just about the airstrikes."