President Bashar Assad on Tuesday ordered a new general amnesty, a day after an offer of "national dialogue" to end Syria's deadly unrest and as a huge crowd rallied in Damascus in his support.

"President Assad has issued a decree granting a general amnesty for crimes committed before the date of June 20, 2011," state news agency SANA announced without giving details.

Tens of thousands of people rallied Tuesday in central Damascus in support of President Bashar Assad, a day after he offered a national dialogue to end Syria's political crisis, an Agence France Presse correspondent said.

Omeyyades Square was turned into a sea of pro-Assad demonstrators, waving Syrian flags and the president's portrait, chanting, "We will sacrifice ourselves for you, Bashar!"

Kuwaiti opposition lawmakers have vowed to keep up their campaign to oust the prime minister who faces a key no-confidence vote on Thursday for having boosted ties with Iran.

"Yes, we have an agenda to rescue Kuwait from (Prime Minister Sheikh) Nasser Mohammed al-Ahmad Al-Sabah who has destroyed the country," veteran opposition MP Ahmad al-Saadun told a gathering on Monday night.

Two car bombs ripped through a guard post outside the local governor's home in the central Iraqi city of Diwaniyah on Tuesday, killing at least 21 policemen, officials and a medic said.

A police colonel said the governor of Diwaniyah province, Salam Hussein Alwan, had been the target of the attack but was late in leaving home and thus escaped unharmed, as did his family.

Turkish President Abdullah Gul has said that Syrian President Bashar al-Assad should transform the autocratic regime in his country into a multi-party system, following a televised address by the Syrian leader to the nation Monday.

Gul told reporters late on Monday that Assad’s speech was “not enough.”

Toppled Tunisian president Zine el Abidine Ben Ali and his wife were sentenced in absentia Monday to 35 years in prison each in a trial for misappropriating public funds, a judge said.

Judge Touhami Hafi also fined the exiled ex-leader 50 million dinars (25 million euros) and his wife Leila Trabelsi 41 million dinars on the first day of the trial.

Italy's foreign minister warned Monday that NATO's accidental killing of civilians in the Libyan air war was endangering the alliance's credibility.

"NATO's credibility is at risk," Franco Frattini told reporters on the sidelines of a meeting of European Union foreign ministers in Luxembourg.

The United States on Monday demanded "actions, not words" from Syrian President Bashar al-Assad who said dialogue could lead to a new constitution and even end his Baath Party's monopoly on power.

"What's important now is action, not words," State Department spokeswoman Victoria Nuland said after Assad addressed the demands of pro-democracy protesters who have been violently repressed. "A speech is just words."

Syrian authorities on Monday showed journalists and ambassadors a "new mass grave" that military sources said contained at least 29 bodies near the restive northern town of Jisr al-Shughour.

An Agence France Presse photographer who was among a group of journalists taken by the authorities to the area said he counted eight bodies which were removed from a rubbish dump.

"Outraged" European ministers on Monday agreed to beef up sanctions on President Bashar al-Assad as they cast doubt on his latest offers of change, some demanding he "reform or step aside".

Amid continuing bloodshed in Syria's crackdown on protesters, European Union foreign ministers also angrily demanded action at the United Nations and slammed Russia's resistance to any such move.