Yemeni President Ali Abdullah Saleh, in power since 1978, said on Monday that only defeat at the ballot box will make him quit, as he faced growing calls to step down.

"If they want me to quit, I will only leave through the ballot box," Saleh told a news conference as thousands of protesters, including opposition MPs, gathered outside Sanaa University to demand his departure.

Sudanese President Omar al-Bashir will not stand for reelection, an official at his National Congress Party said on Monday, while insisting he was "not under pressure" from the wave of protests rocking the Arab world.

"I can confirm, 100 percent, that Bashir is not going to run for president in the next election. He will actually give a chance to different personalities to compete for the position," Rabie Abdul Ati told Agence France Presse.

A car bomb detonated by a suicide attacker in the central Iraqi city of Samarra killed 10 policemen and wounded 16 others on Monday morning, police said.

The bomber rammed his explosives-packed vehicle into a compound for an emergency response unit which had been moved to the city to help with security for Shiite mourning rituals earlier this month, a police officer said.

Tunisia's interim government on Sunday asked Saudi Arabia to extradite deposed strongman Zine El Abidine Ben Ali as it faced a second day of protests demanding its resignation.

Prime Minister Mohamed Ghannouchi's government made the official request to Riyadh, where Ben Ali fled on January 14 with his family after weeks of popular revolt against his 23-year regime, said a foreign ministry statement cited by state news agency TAP.

Anti-regime protests spread closer to the Libyan capital Sunday amid new fighting in the flashpoint city of Benghazi, as Human Rights Watch said it feared a catastrophe with more than 170 people dead in an iron-fisted crackdown.

As the death toll continued to rise, world leaders stepped up their pressure over strongman Moammar Gadhafi's response to the unprecedented challenge to his four-decade rule of the oil-rich North African country.

Hundreds of stateless Arabs demonstrated for the third day running on Sunday to press for basic rights and citizenship of the oil-rich Gulf state, an Agence France Presse photographer said.

Up to 300 protesters took to the streets in al-Jahraa, west of Kuwait City and around 200 demonstrated in Sulaibiya, south west of the capital, and the two protests remained peaceful unlike the previous two days.

Jordan's King Abdullah II on Sunday urged speedy reforms, comprehensive dialogue and more efforts to battle corruption amid popular discontent and pro-reform protests.

"When I talk about reform, it means that I want real and fast reforms," the king told government officials, MPs, senators and members of the judiciary, the state-run Petra news agency reported.

Thousands staged rallies in Moroccan cities on Sunday demanding political reform and limits on the powers of King Mohammed VI, the latest protests demanding change that have rocked the region.

Between 3,000 and 4,000 people took to the streets of the capital Rabat, shouting: "The people want change, denouncing corruption and calling for a democratic constitution to be adopted.

Hundreds of students demonstrated on Sunday on the eighth straight day of anti-regime protests in Sanaa, while police shot dead a protester in south Yemen and the opposition vowed to join protests.

In the capital, students gathered outside the university's campus chanting slogans demanding the ouster of President Ali Abdullah Saleh, in power for 32 years, an Agence France Presse correspondent said.

Faezeh Hashemi, daughter of Iran's ex-president Akbar Hashemi Rafsanjani, was freed on Sunday after being arrested briefly in Tehran as police deployed to prevent protests, Fars news agency reported.

"Faezeh Hashemi, who was arrested as she led a number of anti-revolutionaries and rioters while claiming to purchase clothes in Vali Asr Street, has been released," the report said.