Syria has warned the United States of retaliatory measures if Washington launches another incursion into the country's territories.

"We would defend our territories" if the US repeats such a "criminal and terrorist aggression" against Syria, Foreign Minister Walid al-Moallem said on Monday, a day after US commandoes launched a cross-border attack on a small Syrian border town.

During the raid, the commandoes onboard four helicopters killed at least eight people, including four children in the village of al-Sukkiraya.

"We put the responsibility on the American government. Killing civilians in international law means a terrorist aggression," the Foreign Minister said in a press conference in London, after talks with his British counterpart David Miliband.

The US confirmed the attack on Monday, saying the invasion had been a 'successful' operation against 'foreign fighters' in Syria.

SB/DA