Yemeni soldiers killed four protesters and wounded seven others on Friday when they opened fire on an anti-regime rally in the northern province of Amman, officials and Shiite rebels said.

The shooting, which came a day after the opposition and clerics offered embattled President Ali Abdullah Saleh a smooth exit from power, took place in the village of Semla, 170 kilometers from the capital Sanaa.

Libyan forces carried out an air strike on the edge of the rebel-held town of Ajdabiya Friday, as opponents of veteran leader Moammar Gadhafi called for fresh protests in the capital Tripoli.

U.S. President Barack Obama said all options were on the table for driving Gadhafi out of power as the strongman's son said air strikes on rebel-held positions were scare tactics rather than to inflict serious damage.

Interim Tunisian President Foued Mebazaa on Thursday announced that a constituent assembly charged with developing a new post-revolt constitution will be elected on July 24.

"We declare today the start of a new era ... in the framework of a new political system that breaks definitely from the deposed regime," Mebazaa said in a televised address to the nation.

U.S. President Barack Obama said Thursday he is examining the "full range" of military options, including a no-fly zone, if the revolt in Libya turns into a bloody stalemate and humanitarian disaster.

Accusing Moammar Gadhafi of encouraging violence against his citizens, Obama again called on the Libyan leader to stand down for the good of his country.

The Libyan opposition on Thursday flatly rejected a mediation proposal by Venezuelan President Hugo Chavez to find a peaceful solution to the crisis in the country, a spokesman said.

"We have a very clear statement. It's too late. Too much blood has been spilt," Mustafa Gheriani, a spokesman for the opposition's self-declared national council set up in the eastern city of Benghazi, told Agence France Presse.

The U.S. military is not opposed to imposing a no-fly zone over Libya, the Pentagon said on Thursday, despite a stream of skeptical comments by defense leaders.

The caution expressed by Defense Secretary Robert Gates and senior officers over a potential no-fly zone or other military action "should not be interpreted as somehow an opposition to doing this," Pentagon press secretary Geoff Morrell told MSNBC television.

Egypt's new military rulers told visiting Turkish President Abdullah Gul Thursday they were committed to overseeing a democratic transition after the overthrow of president Hosni Mubarak.

"The Supreme Council of the Armed Forces reiterated its will to manage a democratic transition," Gul told reporters.

Libya is on the verge of civil war, Russian President Dmitry Medvedev said on Thursday, in one of the starkest warnings yet by a world leader over the situation in the country.

"This is an extreme situation," he told Russia's Emergencies Minister Sergei Shoigu, according to state news agency ITAR-TASS.

Cyber activists have created a group on Facebook calling for a "Day of Anger" on Friday in the eastern Shiite-majority Saudi region, following the arrest of a Shiite cleric.

The group of more than 500 members is calling for protests after Friday prayers in Al-Hufuf, in Eastern Province's Al-Ihsaa governorate, to demand the release of Sheikh Tawfiq al-Amer.

A suicide bomber blew himself up inside a bank in the northwestern Iraqi city of Haditha on Thursday, killing nine people including three policemen, the town's mayor said.

Eight other people, all civilians, were wounded in the midday blast at a branch of the state-owned Al-Rafidain bank in Haditha, 210 kilometers northeast of Baghdad, Mayor Bassim Naji said.