An exiled cousin of Syrian President Bashar al-Assad warned his regime Monday it only had a "small window of opportunity" to introduce reform or face being overthrown by a mounting protest movement.

"You have to move very quickly. This is a very small window of opportunity," Ribal al-Assad, head of the London-based Organization for Democracy and Freedom in Syria, urged the Middle East state in an interview with Agence France Presse.

The U.N. Security Council began a closed-door meeting on Libya Monday, diplomats said, amid rising international criticism of air strikes directed at the regime of Moammar Gadhafi.

Missile and air strikes launched over the weekend by U.S., British and French forces targeted Libyan air defense systems to impose a no-fly zone on Gadhafi's forces, and on Sunday demolished a building in the Libyan leader's compound.

Libyan government forces pulled back 100 kilometers from rebel-held Benghazi but showed they still had plenty of fight on Monday as they easily beat off a rebel advance.

The forces loyal to Libyan leader Moammar Gadhafi had retreated overnight to the key town of Ajdabiya, south of the city of Benghazi, after Western-led air strikes destroyed much of their armor, leaving dozens of wrecked tanks along the road.

Russian President Dmitry Medvedev on Monday slammed Prime Minister Vladimir Putin's comments on military action against Libya as "unacceptable", in the most public clash yet between Russia's ruling tandem.

Putin earlier Monday denounced the U.N. resolution allowing military action on Libya as resembling a "medieval call to crusade", in one of his most virulent diatribes against the West in years.

Thousands of Syrians marched Monday in the southern town of Daraa after the funeral of a protester killed in the previous day's demonstration inspired by revolts in Tunisia and Egypt, a resident said.

The resident said "a mass of demonstrators started to march from the cemetery towards Al-Omari mosque after the burial" of Raed Akrad, who was killed by security forces on Sunday when they used live ammunition to break up a protest.

Jordan's Islamists urged King Abdullah II on Monday to carry out reforms similar to measures taken this month by his Moroccan counterpart, saying there was no need for a dialogue commission.

"King Abdullah knows the meaning of real reform, which does not need a committee to initiate dialogue," Zaki Bani Rsheid, head of political office of the Islamic Action Front (IAF), told Agence France Presse.

Tanks were deployed in the Yemeni capital on Monday as top generals pledged allegiance to the "revolution" and the country's main tribal leader demanded President Ali Abdullah Saleh's exit from power.

Tanks took up positions in key locations across Sanaa including at the presidential palace, the central bank and the ministry of defense, but it was unclear what their orders were or who was in command.

Human Rights Watch Monday accused Syrian authorities of using "excessive force" in a crackdown on anti-regime protesters that killed five people over the past three days.

The U.S.-based rights watchdog said in a statement that "Syria should cease use of live fire and other excessive force against protesters" following the violence in Daraa, 100 kilometers south of the capital Damascus.

Bahrain has foiled a "foreign plot" to target Gulf countries, King Hamad said in a possible reference to Iran, after security forces crushed Shiite-led unrest, the state news agency reported Monday.

He said there was a "foreign plot being prepared over a period of 30, maybe 20 years... so that if it works in one of the Gulf Cooperation Council countries, it could spread," the king was quoted as saying.

Embattled Yemeni President Ali Abdullah Saleh sacked his government on Sunday as mourners massed in Sanaa to bury many of the 52 people gunned down by his loyalists, and more regime figures quit over the killings.

Tens of thousands of people turned out for the funerals in what witnesses said was the largest gathering of Saleh's opponents since protests against his autocratic regime erupted in late January.