Embattled Libyan leader Moammar Gadhafi said in an audio message relayed to supporters on Friday that his regime will not fall and told NATO to stop attacking his troops.

"The regime in Libya will not fall -- it is based on the people, not on Gadhafi. NATO is wrong if it thinks it can topple the regime of this country," he said in the message to thousands of supporters in Sabha, some 750 kilometers south of Tripoli.

Fearing an acute shortage of medical and other essential supplies, Libya's rival factions are in talks with the United Nations to ease international sanctions on the war-torn nation, Agence France Presse has learned.

Well-placed U.N. officials said representatives from Libya's rebel council and Moammar Gadhafi's regime held talks last week with the World Health Organization aimed at drawing up a list of items for sanctions relief.

Tens of thousands rallied in Sanaa on Friday to "reject" Yemen's dependence on the United States and Saudi Arabia, saying badly burned President Ali Abdullah Saleh was "politically dead" after a TV appearance.

Meanwhile, thousands of Saleh supporters staged a rival rally in the capital's southern district on what they have named "The Friday of thanks" over Saleh's health, chanting "The people want Ali Abdullah Saleh."

At least 13 Syrian protesters were killed and 40 others wounded on Friday across the country as nearly half a million people demonstrated in the protest hub of Hama, activists said.

Rami Abdul Rahman, chief of the Syrian Observatory for Human Rights, said that at least 450,000 Syrians rallied after Friday prayers in Hama under the banner "No to dialogue" with President Bashar al-Assad's regime.

Both the U.S. and French ambassadors to Syria were in the protest hub of Hama on Friday to observe anti-regime rallies there as nearly half a million people demonstrated in the flashpoint central city.

The move prompted the Syrian government to accuse the U.S. ambassador to Damascus, Robert Ford, of meeting "saboteurs" in Hama and inciting protests against President Bashar al-Assad.

Thousands of people took to the streets across Egypt on Friday to defend the uprising that toppled president Hosni Mubarak, directing their anger at the new military rulers over the slow pace of reform.

Flag-waving protesters converged on Cairo's Tahrir square to push for democratic change and demand that former regime officials accused of abuse be brought to justice.

Scores of pro-Palestinian protesters trying to reach Israel were blocked at airports in Europe and two American activists who arrived in Israel were deported early Friday, Israeli officials said.

Israel increased security at the Ben-Gurion International Airport ahead of the activists' arrival and asked foreign airlines to prevent blacklisted travelers from boarding Israel-bound flights, as hundreds said they would travel to Israel to protest Israeli policies toward the Palestinians.

German Chancellor Angela Merkel Friday defended her government's silence on a reported secret deal to sell hundreds of tanks to Saudi Arabia, and said she was committed to democracy in the region.

"Deliberation and decisions by the federal security council are secret for good reason," she told the daily Mittelbayerische Zeitung, referring to the panel including the chancellor and top ministers that rules on arms exports.

The United States and Iraq are negotiating the possibility of keeping some U.S. forces in the country beyond a December 31 deadline for withdrawal, the U.S. military's top officer said Thursday.

"The negotiations are ongoing and it's hard," Admiral Mike Mullen told reporters at a Pentagon Press Association event.

The U.S. ambassador to Damascus is visiting the flashpoint Syrian city of Hama and plans to observe mass demonstrations Friday against President Bashar al-Assad's regime, the State Department said.

Last Friday, an anti-regime rally brought out half a million people in Hama, according to pro-democracy activists. The security services did not intervene and Assad fired the city's governor the next day.