Iran has had forces in Syria as "advisers," the commander of Iran's Islamic Revolutionary Guard Corps said Sunday, according to the semi-official Fars news agency.
A spokesman for Iran's foreign ministry said the country has no such personnel in Syria now.
Here are key developments in the Syrian civil war:
The Quds Force, the elite special operations unit of Iran's Islamic Revolutionary Guard Corps, has long had activities in Syria and Lebanon, the commander of the corps said Sunday.
Asked at a news conference whether Iran has a presence in Syria, Gen. Mohammad Ali Jafari said Iran has not taken military action in the country but has provided guidance and "advisers," Fars reported.
"He said the very few IRGC Quds force members who had some time in the past been in Lebanon or Syria did not serve as military or combat troops, alluding that their presence was aimed at a transfer of knowledge and experience," Fars reported.
Jafari contrasted that against what he called "other countries' overt military assistance to Syria's opposition groups," according to Fars.
"If Syria comes under attack, Iran's decision to get involved militarily will depend on the circumstances," he added.
Iran has openly supported the Syrian regime throughout the conflict.
Fars reported that, according to Jafari, Tehran is "giving advice and spiritual assistance to Bashar al-Assad's government."
A spokesman for Iran's Foreign Ministry, however, told CNN on Sunday that no members of Iran's military or Quds forces are currently in Syria.
"We are in communication with the Syrian government just like we are with all of our friends in the region," spokesman Ramin Mehmanparast said.
Last month, U.S. Defense Secretary Leon Panetta accused Iran of training pro-regime militias in Syria in an increased effort to to prop up embattled Syrian President Bashar al-Assad.
Anti-violence opposition groups meet
Twenty-four groups that oppose the Syrian regime but also oppose a violent uprising gathered Sunday at a Damascus hotel.
The groups discussed a need to begin dialogue with the Syrian government -- even as shells could be heard falling.
The groups planned to meet with Lakhdar Brahimi, the new U.N. and Arab League envoy to Syria.
It was the first meeting of these groups.
The number of people killed Sunday in Syria has risen to 167, the opposition Local Coordination Committees of Syria said.
At least 60 were killed in and around Damascus and at least 50 in Aleppo, the group said.
There were fierce clashes between the Free Syrian Army and government forces in Aleppo, accompanied by heavy aerial shelling, the group said.
In Idlib, indiscriminate shelling killed 12 people, including five children, and wounded several others, the LCC said. More than 20 homes were burned and destroyed, the group said.
Warplane shelling on a neighborhood near a hospital in Aleppo left at least 11 dead, LCC said. An explosive device went off in a passenger bus in Daraa province killing seven people, the LCC said. The incident occurred in Khirbet Ghazaleh. A military strike that hit a bakery in the Idlib province town of Kafr Owied killed six people.