(CNN) -- A Syrian diplomat left the government and ruling party Wednesday, appealing to the military to stop killing its "fathers, sons and sisters" and instead direct its artillery fire toward the "criminals" of the Syrian regime.
The defection of Nawaf al-Fares, Syria's ambassador to Iraq, follows the defection last week of a brigadier general in protest of the killing of his fellow Sunnis. Al-Fares is the highest-ranking diplomat so far to leave the regime.
He also announced his defection from the ruling Baath party, becoming the most senior member to leave.
"To my brothers in the military, your military doctrine is to defend the homeland against external aggression and protect its borders," al-Fares said in a video statement taped in front of a Syrian opposition flag and given to the TV network Al Jazeera Arabic. "So did your fathers, sons, and sisters become the enemies now? And are they the ones who you should fight? Is that what you have learned in your military schools?"
Al-Fares said he was joining the revolution. He called the government "malicious" and "the killer of the people."
Neither the Iraqi nor Syrian government immediately commented on the news. Al-Fares was still in Iraq on Wednesday and making his way to a "safe area," according to two members of the Syrian National Council, a main opposition group.
International envoy Kofi Annan visited Iraq on Tuesday as part of efforts to seek an end to the 16 months of violence in Syria. He also visited Iran. Both Iran and Iraq had committed to supporting his six-point peace plan, he said, and both back the idea of a Syrian-led political transition. The United States and other nations oppose Iranian participation in the diplomacy.
"Iran is definitely part of the problem in Syria," said Susan Rice, the U.S. ambassador to the United Nations. "It is supporting, aiding, and abetting the Assad regime materially and in many other ways, and it has shown no readiness to contribute constructively."
Annan, the former United Nations secretary-general who now serves as the U.N. and Arab League envoy to Syria, briefed the U.N. Security Council on the crisis Wednesday.
"The council is now discussing what the next step should be and what action they should take," Annan said. "We should hear something from them in the next few days."
Britain introduced a new resolution Wednesday threatening "immediate measures" if the Syrian government doesn't comply with elements of Annan's six-point peace plan, introduced in March.
Russia and China -- which are permanent Security Council members, along with Britain -- oppose putting such pressure on the al-Assad regime. Russia put forward its own draft Wednesday urging all parties to cease violence and calling for an extension of the U.N. observer mission in Syria for three months.
Annan acknowledged that efforts to stop the carnage in Syria have so far failed. He said he is urging all the governments to work together in pursuit of common interests.
"If we can speak with one voice, that voice is much more powerful," he said. "We all want to protect the Syrian people, we all want to see an end to the violence, we all want to make sure ... the conflict doesn't spread to the region."
His briefing came a week before the council must decide what to do with 300 U.N. observers who have been unable to do their work because of the violence.
Russia and China have previously vetoed U.N. Security Council draft resolutions that would have formally condemned the Syrian regime. Many other nations said such resolutions could have pushed al-Assad to stop the bloody, sustained crackdown on dissidents seeking his ouster.
Speaking ahead of Annan's Security Council briefing, Germany's U.N. ambassador, Peter Wittig, told reporters that it was "a mistake" to focus on the question of the monitors in isolation.
"We want compliance with the decisions of the Security Council and we want to see the stop of (the use of) heavy weapons," he said.
Opposition groups say more than 15,000 people have died since the violence began, while the United Nations has put the death toll at more than 10,000. At least 78 people killed across the country Wednesday, the opposition Local Coordination Committees of Syria said.
In another development Wednesday, the head of the Syrian National Council, Abdul Basit Sieda, visited Russia's foreign minister -- a notable meeting between a major Syrian opposition group and a government that some opposition members have accused of backing the Syrian regime.