MOSCOW SCEPTICAL

After talks with NATO foreign ministers in Brussels, Russian Foreign Minister Sergei Lavrov repeated Russian concerns that the Syrian conflict was becoming increasingly militarised and accused NATO of over-reacting.

"Yes, there were artillery strikes but we believe that they were not intentional," he told a news conference.

Russia, which has a fractious relationship with the military alliance, has been at odds with NATO over how to end the war and has vetoed UN resolutions aimed at pressuring Syrian President Bashar al-Assad to step down.

Rasmussen said Patriot missiles would be effective as interceptors, whether attacking missiles carry chemical weapons or conventional warheads.

Asked whether blowing-up a chemical warhead in mid-air could contaminate a wide area, a NATO official said: "Any damage caused by a chemical missile attack that hits its target would be much greater than any possible damage from an intercept."

Britain has told the Syrian government that any use of chemical weapons would have "serious consequences", British Foreign Secretary William Hague said.

US President Barack Obama told Assad on Monday not to use chemical weapons, without saying how the United States might respond.

The United States has collected what has been described as highly classified intelligence information demonstrating that Syria is making what could be construed as preparations to use elements of its extensive chemical weapons arsenal, two US government sources briefed on the issue said.

Western military experts say Syria has four suspected chemical weapons sites, and it can produce chemical weapons agents including mustard gas and sarin, and possibly also VX nerve agent.

Syria said on Monday it would not use chemical weapons against its own people and Russia's Lavrov was sceptical about the media reports that Syria was willing to use its stockpile.

"It is not the first time that the messages appear ... that Syrian authorities are transferring their stockpiles of chemical weapons to other places or that they are willing to apply these weapons," he said, according to an interpreter.

Moscow checked such reports, but "every time we get confirmation that nothing of this sort is being prepared," he said.

NATO officials have said repeatedly the alliance has no intention of getting involved in Syria's civil war, but they are concerned about the situation on its border with Turkey.

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