The United Nations has made plans to assemble a peacekeeping force for Syria if a ceasefire proposed by a special envoy takes hold, a top U.N. official said Monday.

U.N. peacekeeping chief Herve Ladsous stressed however that planning was very tentative while fighting rages in Syria and would be dependent on the U.N. Security Council overcoming its bitter divisions on the 19-month-old conflict.

Hopes of a truce being implemented in war-torn Syria during this week's Muslim Eid holidays are "slim," the Arab League said on Monday, as rebels and troops engaged in fierce clashes in Damascus and on northern battlefields.

But the United Nations held on to the hope that the two warring sides will observe a truce during the four-day Eid al-Adha holiday which begins on Friday, saying it had plans to assemble a peacekeeping force if a ceasefire takes hold.

Russian deputy Foreign Minister Mikhail Bogdanov arrived in Tehran on Monday to discuss the crisis in mutual ally Syria with Iranian officials, Fars news agency reported.

"Mikhail Bogdanov, deputy foreign minister for Middle East and President Vladimir Putin's special representative arrived in Tehran at the invitation of his counterpart Hossein Amir Abdolahian to discuss regional issues and Syria," Fars said.

A Jordanian soldier was killed before dawn on Monday in a clash with militants trying to cross the border into neighboring Syria, the Information and Culture Minister Samih Maaytah told AFP.

He said that "corporal Mohammed Abdullah al-Munasir, 25 years old, was martyred during a clash with an armed group that wanted to enter Syria."

The head of the Syrian National Council Abdel Basset Sayda accused the Syrian regime of being behind the assassination of Internal Security Forces Intelligence Bureau head Brigadier General Wissam al-Hasan, reported al-Joumhouria newspaper Monday.

He warned: “The Syrian regime will commit more assassinations in Lebanon in order to create unrest in the country and cover up its crimes in Syria.”

After days of cramming, two intense earlier debates, and a bitter months-long campaign, Barack Obama and Mitt Romney will come out swinging Monday in their third and final showdown.

With this rematch focusing on foreign policy, the president and his Republican rival will no doubt trade blows over security shortcomings in Libya; how to contain Iran; the roiling crisis in Syria; a rising China; and ending the Afghan war.

The United States will help Lebanon investigate the car bombing in Beirut that killed Internal Security Forces Intelligence Bureau head Brigadier General Wissam al-Hasan, a staunch critic of Syria, the State Department said Sunday.

Secretary of State Hillary Clinton spoke by phone Sunday with Prime Minister Najib Miqati to again condemn Friday's attack that killed Hasan and two others, department spokeswoman Victoria Nuland said.

Ten people were killed and 15 others wounded on Sunday when a bomb exploded outside a police station in the Christian neighborhood of Bab Touma in the Syrian capital Damascus, a rights group said.

The Syrian Observatory for Human Rights gave a toll of 10 dead and 15 wounded as a car bomb blew up outside the station in Bab Touma, where many in the minority community fear Islamists in the anti-Assad revolt.

Lebanese Forces leader Samir Geagea demanded on Saturday the suspension of all the agreements with Syria, the expulsion of Syrian Ambassador to Lebanon Ali Abdul Karim Ali and the immediate resignation of the cabinet.

“They assassinated (ISF Intelligence Bureau head Brigadier General Wissam) al-Hasan to prevent the work of the Special Tribunal for Lebanon from revealing the truth,” Geagea said in a news conference at his Maarab residence.

Phalange Party MP Sami Gemayel considered on Saturday that Lebanon entered an open confrontation with the Syrian regime.

“We tried to disassociate our nation from the conflict in Syria, but the regime is challenging the Lebanese people once again by assassinating (ISF Intelligence Bureau head Brigadier General Wissam) al-Hasan,” Gemayel said.