Syrian forces launched new air strikes and shelled rebel strongholds in several key cities on Saturday, a watchdog said, after the U.N. named a new envoy to try to end the conflict.

The intensified fighting, particularly in and around the key northern hub of Aleppo, has sent thousands more Syrians fleeing into neighboring countries as the divided international community appears powerless to act.

The Syrian economy has been hit hard by more than 17 months of revolt but may still hold on despite international sanctions with the help of friendly countries such as Russia, Iran and Iraq, experts say.

All economic indicators in Syria, where President Bashar Assad is trying to crush an uprising against his rule, are in the red: the economy is contracting, inflation rates have skyrocketed, unemployment has risen and the current account deficit continues to increase.

Interior Minister Marwan Charbel stressed on Saturday that Turkish officials are keen to resolve the case of the abducted Lebanese pilgrims in Syria.

“We agreed on continuing the mutual efforts in another meeting, scheduled to be held soon, to follow up the case,” Charbel’s press office said in a statement.

President Michel Suleiman hoped on Friday that no Syrian officials are linked to the attacks that were being planned in Lebanon by former minister Michel Samaha, reported As Safire newspaper on Saturday.

“I enjoy good ties with Syrian President Bashara Assad. I have nothing to hide. What I am most concerned about is the discovery of explodes in Samaha’s possession,” he said in response to being asked if the Syrian president had contacted him after the former minister’s arrest.

Russia welcomed the new international envoy for the conflict in Syria and said it expected him build on the work of predecessor Kofi Annan, the Foreign Ministry said in a statement Saturday.

"We proceed on the assumption that Lakhdar Brahimi will base his work on the platform of the existing 'road map' of a Syrian settlement -- Kofi Annan's peace plan and the final communique of the June ministerial meeting of the Action Group on Syria in Geneva and also on the relevant U.N. Security Council resolutions," the ministry said.

Russia on Friday rejected a proposal to set up no-fly zones to help civilians flee fighting in Syria's border areas after the United States said it was ready to consider the move.

"You have to solve citizen security issues using methods put in practice by international humanitarian law," Foreign Minister Sergei Lavrov told Sky News Arabia in an interview to be aired in full on Saturday and released to Russian media.

Lakhdar Brahimi, a veteran Algerian diplomat, will take over from Kofi Annan as the international envoy on the Syria conflict, the United Nations said Friday.

U.N. leader Ban Ki-moon appealed to the divided international powers to give "strong, clear and unified" support to the new envoy.

Turkey advised its nationals on Friday to avoid non-essential travel to Lebanon after mass kidnappings which included two Turkish citizens, the foreign ministry said.

"It is deemed beneficial if our citizens avoid traveling to Lebanon unless absolutely necessary," said the ministry in a statement.

Humanitarian workers are being caught up in the fighting in Syria, threatening the supply of emergency medical aid to Syrian civilians, the British Red Cross said on Friday.

"Some of the worst fighting is now in Aleppo, and aid workers are at daily risk in the city," the charity said.

The head of the Independence Movement Michel Mouawad noted on Thursday that the latest developments in Lebanon are aimed at imposing Lebanon under the rule of Hizbullah’s arms and changing its identity by force.

He added during an Independence Movement iftar: “We reject the employment of Zgharta’s name in defending the criminal Syrian regime.”