Putin told reporters on Saturday it was "utter nonsense" to suggest Syrian President Bashar al-Assad's regime would use chemical weapons while it was winning the war against the rebels.

He called on the US to release its evidence regarding last week's alleged chemical attacks on a Damascus suburb, which Washington claims killed over 1,400 people.

"Regarding the position of our American colleagues, friends, who affirm that government troops used weapons of mass destruction, in this case chemical weapons, and say that they have proof, well, let them show it to the United Nations inspectors and the Security Council," he said.

"I am convinced that it [the chemical attack] is nothing more than a provocation by those who want to drag other countries into the Syrian conflict, and who want to win the support of powerful members of the international arena, especially the United States," Putin added.

It was the Russian president's first public reaction to a US intelligence report released on Friday which said US authorities were convinced that Assad's forces were behind August 21 attacks.

"Our high confidence assessment is the strongest position that the US intelligence community can take short of confirmation," the report said.

It cited "a large body of independent sources" who reported that 1,429 people were killed, considerably more than first estimated. The report also specified that 426 of the dead were children.

UN findings expected

The Syrian government has firmly rejected allegations it was behind the chemical attacks, placing the blame on opposition forces.

A group of UN inspectors investigating the alleged use of chemical weapons left Syria on Saturday and arrived in The Hague, Netherlands.

The team was tasked with carrying out probes at three sites in Syria, including last week's alleged target.

UN spokesman Martin Nesirky told reporters in New York on Saturday that UN Secretary-General Ban Ki-moon would be briefed by the head of the inspection team, Ake Sellström, on Sunday. Nesirky did not give a timeline for when the inspectors would present their results. But he said that the team would conduct an impartial and credible investigation.

Any UN findings will not identify culpability. The investigators have a mandate only to check whether chemical weapons were used.

When asked by reporters if the secretary-general would seek to expand the inspectors' mandate, Nesirky said that the mandate had been established by the General Assembly and approved by the Security Council.

"The mandate is the mandate. The team and the secretary-general will abide by that mandate….," the UN spokesman said.

"The mandate is robust and provides for the United Nations to provide in an impartial and credible manner a picture of what happened," he continued.

US debates military action

In a press conference on Friday, US President Barack Obama said he was looking at a "wide range of options" for military intervention in Syria. He however stressed that none of them would involve putting "boots on the ground."

The US president said a long-term campaign was out of the question.

France was the only permanent member of the UN Security Council, besides the United States, to immediately state a readiness to intervene in Syria.

President Francois Hollande had told the Friday edition of the newspaper "Le Monde" that he and Obama "agreed that the international community cannot tolerate the use of chemical weapons, that it should hold the Syrian regime accountable for it and send a strong message."

Britain, another permanent member, has ruled out military action following a parliamentary vote, while Russia, perhaps Syria's closest ally during the civil war, has vowed to block any action against the Syrian regime in the UN Security Council.

Germany is also not expected to take part in military action. Foreign Minister Guido Westerwelle said Friday that Berlin was unlikely to send troops or planes to the embattled nation.

"No one has asked us to take part in such an action, nor are we considering it," Westerwelle said when asked about the possibility of military action in Syria.

ccp,slk/pfd (AFP, Reuters)