The United States and Gulf Arab states on Saturday urged envoy Kofi Annan to produce a "timeline for next steps" in his peace plan for Syria if President Bashar Assad fails to stop the bloodshed.

U.S. Secretary of State Hillary Clinton, who met her counterparts from Saudi Arabia, Kuwait, Bahrain, Qatar, the United Arab Emirates and Oman at a meeting in Riyadh, voiced concern over Syria's continued deadly crackdown on dissent.

Expectations are low of an international conference Sunday in Istanbul having much impact on the Syrian crisis, as discord among the so-called "Friends of Syria" outweighs their agreements.

More than 70 representatives from Western and Arab countries will gather to craft a solution aimed at halting the killing in Syria, after more than a year that has left between 9,000 and 10,000 people dead in a crackdown on dissent by Bashar Assad's regime.

At least 16 people were killed on Saturday in new clashes between the Toubou people and Arab tribesmen in the southern Libyan desert oasis of Sabha, local and medical sources told Agence France Presse.

A doctor at Sabha hospital, treating Arab casualties, said eight people were killed and another 50 wounded in fighting between the early morning and noon. A Toubou tribal source said eight of their people were also killed.

Violence across Syria killed at least 25people on Saturday as security forces fired at a Damascus funeral for protesters who died the previous day during demonstrations, monitors said.

The Syrian Observatory for Human Rights said a child was killed on Saturday by rocket fire in the Bayada area of Homs, where troops fired shells at rebels in its Khaldiyeh district at the rate of one a minute.

Iraq may not participate in the "Friends of Syria" conference in Istanbul on Sunday as it wants to maintain its ability to serve as a mediator, the Iraqi prime minister's spokesman said.

"We want to maintain our mediation role, and the role of mediator sometimes requires not participating in this conference or that," Ali Mussawi told Agence France Presse.

Gunmen killed a 22-year-old protester near the Bahraini capital early on Saturday, said the main Shiite opposition group al-Wefaq, blaming militants loyal to the regime.

Ahmad Ismail Hassan was wounded in the stomach when men in civilian clothing fired on protesters calling for "democracy and an end to dictatorship" in Salmabad, on the southern outskirts of Manama, al-Wefaq said in a statement.

Amnesty International on Saturday urged Jordan to free six political activists charged with insulting King Abdullah II, saying that at least three of them were beaten during interrogation.

The human rights watchdog "is calling for the immediate and unconditional release of six pro-reform activists held for 'insulting' the king," it said in a statement.

Israel's U.N. ambassador said Friday that his government has made no decision yet on whether it will attend a proposed international conference on a nuclear weapons free Middle East.

But the envoy, Ron Prosor, insisted there could be no accord on a weapons free zone until there is a "comprehensive peace" in the region.

U.S. Secretary of State Hillary Clinton geared up for talks in Saudi Arabia on Saturday about plans for a Gulf missile shield against Iran and ways to press Tehran's ally Syria to stop killing Syrians.

After meeting King Abdullah and other Saudis in Riyadh on Friday, Clinton was to consult with her counterparts from Saudi Arabia and its five Gulf Arab neighbors, all of them U.S. allies.

The bid to overthrow Syria's government is over, and the battle now is to secure stability, foreign ministry spokesman Jihad Makdisi said in a report by state media on Saturday.

"The battle to topple the state is over, and the battle to solidify stability... and move on towards a renewed Syria has begun," Makdisi was cited as saying by the official SANA news agency.