"Part of its legal mandate is to determine when international humanitarian law applies," Maguire told CNN. "We make a determination as to whether a conflict exists."
"In theory," he said, the Red Cross announcement could affect prosecutions by the International Criminal Court in the future. If a prosecuting authority is established for Syria, it could point to the announcement that the Geneva Conventions applied and to ways that they were violated. However, for the court to look at the situation in Syria, a referral from the U.N. Security Council would be required, Maguire noted.
At least 97 people were killed Monday, according to the opposition Local Coordination Committees of Syria (LCC). There were 30 deaths in Hama, 21 in Homs, 13 in Aleppo, 11 in Damascus, eight in Daraa, seven in Deir Ezzor, four in the Damascus suburbs and three in Idlib, the LCC said.
Monday's fighting in Damascus follows what opposition activists called a massacre of more than 200 people in the town of Tremseh, near Hama, last week. But a top Syrian official disputed the death toll and the massacre allegation, telling reporters over the weekend that government troops were fighting armed opposition.
U.N. monitors reported Sunday that the attack appeared to target "army defectors and activists," citing accounts by more than two dozen villagers.
The monitors said Syrian forces began shelling the town on Thursday morning. Soldiers entered after the bombardment, conducting house-to-house searches and demanding identification from the men they found. "Numerous" people were then killed after their identification was checked, and some other men were taken from the village, the monitors said.
The monitors found more than 50 homes that had been burned or destroyed, with "pools of blood and brain matter" seen in several homes. The dead included a Free Syrian Army leader who was shot and doctor and his children who died when their home was struck by a mortar shell, the monitors said in a statement issued Sunday. However, the monitors said the number of dead and wounded in Tremseh remained unclear.
Foreign Ministry spokesman Jihad Makdissi told reporters Sunday that opposition fighters had used the village as a base for attacks on government forces. He said only 37 "gunmen" and two civilians were killed in the operation in Tremseh and that no heavy weapons or aircraft were used, according to comments carried by the state-run Syrian Arab News Agency.
CNN cannot confirm details of reported violence because Syria has restricted access to the country by international journalists.
Amid the ongoing fighting, U.N.-Arab League envoy Kofi Annan headed to Moscow for talks with the Syrian government's leading ally. Annan met Monday with Foreign Minister Sergey Lavrov and is set to hold talks on Tuesday with President Vladimir Putin, Annan spokesman Ahmed Fawzi told CNN.