Police gunfire killed four people as the biggest protests yet swept impoverished Yemen, demanding that President Ali Abdullah Saleh step down after three decades in power.

At least 19 people have now been killed in almost daily clashes at anti-regime protests since February 16, according to an AFP tally based on reports by medics and witnesses as calls gather steam for Saleh quit.

The U.N. Human Rights Council unanimously called Friday for Libya to be suspended from the body and for a probe into violations by the regime, in a dramatic session which witnessed the defection of Tripoli's envoy.

In a resolution adopted by consensus, the 47-member U.N. body decided to "urgently dispatch an independent, international commission of inquiry ... to investigate all alleged violations of international human rights law in Libya."

An embattled Moammar Gadhafi said he would throw open the country's arsenals to his supporters in a rabble rousing speech Friday that presaged a bloody battle for the Libyan capital.

In a brief but chilling address in Tripoli's Green Square, Gadhafi told hundreds of cheering supporters from the top of a building to prepare themselves for a fight.

German Chancellor Angela Merkel berated Israeli Prime Minister Benjamin Netanyahu for failing to advance peace talks during a "tense" phone call, Israeli daily Haaretz reported on Friday.

Citing German sources, the newspaper said Merkel responded furiously when Netanyahu criticized Germany for supporting a Palestinian-drafted United Nations Security Council resolution against Israeli settlement construction.

Loyalists of Moammar Gadhafi killed several people in shooting that was spreading through Tripoli on Friday as French President Nicolas Sarkozy said the embattled Libyan leader "must go."

And as protesters against Gadhafi's iron-fisted four-decade rule braved deadly gunfire in several parts of the capital, opponents braced for a fightback by a regime that has suffered yet more defections.

World oil prices rose further on Friday as supply worries persisted due to escalating unrest in the oil-rich Middle East and North Africa, traders said.

Brent North Sea crude for delivery in April rose 76 cents to $112.12 per barrel, having rocketed the previous day to $119.79 -- the highest level since August 22, 2008 -- before sliding lower as many traders took profits.

Protesters took to the streets across Iraq on Friday to mark a "Day of Rage,” with thousands flooding Baghdad's Tahrir Square as seven protesters died in clashes with police in two northern cities.

Protesters in the capital were forced to walk to the rally site as security forces imposed a vehicle ban, a day after Prime Minister Nuri al-Maliki claimed the demonstrations were being organized by al-Qaida insurgents and loyalists of deposed dictator Saddam Hussein.

The deputy to Osama bin Laden issued al-Qaida's second message since the Egyptian uprising, accusing the nation's Christian leadership of inciting interfaith tensions and denying that the terror network was behind last month's bombing of a Coptic church in Alexandria that killed 21 and sparked protests.

The message Friday from Ayman al-Zawahri, the No. 2 leader of the terror network, comes amid renewed Muslim-Christian tension over the slaying of a Coptic priest and a dispute involving a monastery.

New satellite images released by a U.S. research institute show Syria "tried to become a nuclear power," a senior Israeli defense official said on Friday.

Amos Gilad, director of political military affairs at the defense ministry, told army radio that the new images released by the Institute for Science and International Security (ISIS) proved Syria was seeking nuclear weapons.

Two Iranian warships, the first to enter the Mediterranean from the Suez Canal since 1979, docked at the Syrian port of Latakia on Thursday, an Iranian diplomatic source told Agence France Presse in Damascus.

Israel has put its navy on high alert, denounced the ships' arrival in the region as an Iranian power play and branded their voyage "a provocation."