(CBS/AP) BAGHDAD - Syrian President Bashar Assad has agreed to a new U.N.-brokered peace plan focusing on containing the most violent areas of the country, then expanding to the entire nation, international envoy Kofi Annan said Tuesday.
At a news conference in Iran, Annan said the plan still must be presented to the opposition. But he said Assad suggested trying to calm specific areas a day earlier during talks in the Syrian capital aimed at ending the violence, which activists say has killed more than 17,000 people since March 2011.
"(Assad) made a suggestion of building an approach from the ground up in some of the districts where we have extreme violence to try and contain the violence in those districts and, step by step, build up and end the violence across the country," Annan told reporters in Iran, his first step on a tour of Syria's staunchest allies.
Annan later visited Iraq and met Prime Minister Nouri al-Maliki to discuss ways to end the 16 months of bloodshed.
The conflict in Syria has defied every international attempt to bring peace, including an earlier effort by Annan, and there was no sign that the plan the U.N.-Arab envoy described Tuesday will be a breakthrough. Although the government's crackdown has made Assad an international pariah, he still has the support of strong allies such as Russia, Iran and China.
The international community has little appetite for military intervention of the type that helped bring down Libya's Muammar Qaddafi last year, and several rounds of sanctions and other attempts to isolate Assad have done little to stop the bloodshed.
Annan's latest efforts to reach out to Syrian allies suggest he sees Assad's allies as integral to solving the crisis. Annan's outreach to Iran in particular appeared to oppose the approach of Washington, which has rejected Iran's participation in helping solve the crisis.
Tehran has provided Assad with military and political backing for years, and has kept up its strong support for the regime since the Syrian uprising began.
U.S. State Department spokesman Patrick Ventrell said Washington doubts Iran will be able to play a constructive role.
"If the Iranian regime wants to stop giving direct material support to the Syrian killing machine ... we would welcome that. We're not at that point yet," he said Monday in Washington.
CBS News correspondent Clarissa Ward reports that the prospects for Annan's new plan - even if it gains the backing of Iran - may be limited given that Syrian opposition leaders say his dialogue with Assad's regime and other world powers has lost all credibility.
Opposition figures based in neighboring Turkey tell CBS News that it iscontinuing on a peace plan which would allow Assad to stay in power in any way, and Assad has made it clear he will not step down. (Click on the player above for Ward's full report from Turkey)
Critics said Annan's tour of Syria allies smacked of betrayal.
Rajeh Khoury, a columnist in Lebanon's leading An-Nahar newspaper, wrote that Annan's actions "give the Syrian regime more time to accomplish the impossible task of crushing the uprising militarily."
"His insistence on making Iran part of the solution at a time the opposition sees Iran as part of the problem is extremely dangerous," Khoury said.
On Tuesday, Annan said Tehran has offered its support to end the conflict and must be "part of the solution."
"My presence here proves that I believe Iran can play a positive role and should therefore be a part of the solution in the Syrian crisis," Annan told reporters in Tehran after meeting with Iranian Foreign Minister Ali Akbar Salehi.
He said he has "received encouragement and cooperation" from the Iranian government but did not elaborate.
Since Assad took power following the death of his father, Hafez, in 2000, he has deepened cultural, political and economic ties with Iran, making it Syria's strongest regional ally. Tehran, in turn, has boosted Assad's military, providing it with advanced communications technology and weapons, as well as sending elite military advisers.
All of this makes Iran unlikely to support change in Syria.
Annan did not say what kind of involvement he saw for Iran in resolving the crisis, nor did Salehi spell out what Tehran was willing to do to help tame the violence.
Annan brokered a six-point peace plan earlier this year, but it has failed to gain traction on the ground.
Government forces and rebels have widely disregarded a cease-fire that was to begin in April, and spreading violence has kept nearly 300 U.N. observers monitoring the truce stuck in their hotels in Syria.
The U.N. envoy stressed the urgency of finding a solution to the crisis.
"If we don't make a real effort to resolve this issue peacefully and it were to get out of hand and spread in the region, it can lead to consequences that none of us could imagine," he said.
Salehi said Tehran backs the rights of the Syrian people but opposes military intervention. He also blamed the conflict's increasingly chaotic violence on the meddling of foreign powers.
"Unfortunately, the unwise interference of others has caused the situation in Syria to remain critical," he said. "The worsening of the situation should not happen. It would not benefit anyone in the region."
The Syrian conflict has spilled outside the border several times. On Tuesday, the Lebanese army said shells were fired into Lebanon from Syria during an overnight exchange of fire along the countries' frontier.
The Red Cross and Lebanon's NNA state news agency said a Lebanese and two Syrians died one from a heart attack and two others when their motorcycle hit a car in the Wadi Khaled area, where the clashes took place.
The Lebanese government decided at a Cabinet meeting Monday night to boost the army's presence along the volatile border, where shells fired from Syria have killed and wounded several Lebanese in the past few weeks.
Syria says the frontier is being used for smuggling weapons to rebels.