West reaches out to Iran as Syria strategy stumbles

US and Western diplomats scrambled on Saturday to cobble together a diplomatic strategy to end the war in Syria, after the latest humiliating blow to their military plan.

Secretary of State John Kerry and his European counterparts reached out to traditional foe Iran on the sidelines of the UN General Assembly in New York.

Iran and Russia back Syrian strongman Bashar al-Assad, whom Washington sees as the instigator of the civil war that left half his country in the hands of the Islamic State group.

Unwilling to countenance a peace process that would leave Assad in power after he alienated or killed so many of his people, the US has backed small "moderate" rebel groups.

But that strategy appeared in tatters on Saturday after the Pentagon admitted the latest US-trained fighters to cross into Syria had given a quarter of their gear to Al-Qaeda.

A previous 54-strong group that crossed into Syria earlier this year was attacked by Al-Qaeda's local franchise, the Al-Nusra Front, and fell apart, leaving only four or five guerrillas active.

In contrast to the lackluster US effort to shore up its allies on the ground, Russia and Iran have proven good friends to Assad, who clings to power in Damascus.

Iran has dispatched Shiite militia fighters trained and helped by its Revolutionary Guard, and Russia has deployed a powerful military presence to a base on Assad's territory.

With the initiative falling away, Kerry and his allies came to New York hoping to persuade Tehran and Moscow to push for a broad political solution to the conflict.

Kerry and European diplomatic chief Federica Mogherini met separately with their Iranian counterpart Mohammad Javad Zarif.

"I view this week as a major opportunity for any number of countries to play an important role in trying to resolve some of the very difficult issues of the Middle East," Kerry said Saturday, at a joint appearance with Zarif.

"We need to achieve peace and a way forward in Syria, in Yemen, in the region itself and I think there are opportunities this week, through these discussions, to make some progress."

- Without preconditions -

French Foreign Minister Laurent Fabius also planned to meet Zarif, as well as Kerry and the foreign ministers of Turkey, Iraq, Saudi Arabia and of the United Arab Emirates.

The French envoy said he was prepared to talk about Syria without preconditions, but insisted Assad -- whom he blamed for 80 percent of the 240,000 deaths in the war -- would eventually have to go.

"These negotiations cannot start from the premise that Bashar al-Assad will be Syria's eternal future," he said. "But we must engage negotiations."

But, even before his talks with Kerry, Zarif made it clear that Iran's focus is still on the implementation of the nuclear deal it signed in April with five world powers in exchange for sanctions relief.

"We are going to concentrate in this meeting on the full implementation of the Joint Comprehensive Plan of Action," Zarif said, referring to the deal to limit Iran's nuclear ambitions.

"That is the project that we started together and we hope that by its full implementation, its good faith implementation, we can end some of the mistrust that has existed over the past many decades. So that is my priority."

After Kerry's meeting with Zarif, State Department spokesman John Kirby said they had discussed the nuclear deal but that the secretary had "also raised our concerns over the ongoing crises in Yemen and Syria."

Kerry is also due to meet Russian Foreign Minister Sergei Lavrov on Sunday, and President Barack Obama will see President Vladimir Putin during a packed UNGA program.

The US diplomatic drive in New York was weakened right out of the gate by the latest news from the battlefield.

On Friday, the Pentagon admitted a 70-strong group of rebels that it had trained to fight the Islamic State as part of a $500 million program had surrendered much of its equipment, including vehicles and munitions, to the Al-Nusra Front.

US Central Command, which oversees the fight against the IS group, is also facing an investigation into reports it had manipulated intelligence reports to paint a rosier picture of the campaign.