More than a week after an alleged chemical weapons attack killed hundreds of people outside the Syrian capital Damascus, international leaders remain at odds over how to respond to the situation.

Both the United States and Great Britain have said they have no doubt that the regime of President Bashar al-Assad was responsible for the attack. Damascus has consistently rejected accusations that its military carried out the attack, and instead has blamed "terrorist" rebels.

President Assad said on Thursday that Syria would defend itself against any aggression.

"The threats of direct aggression against Syria will only increase our commitment to our deep-rooted principles and the independent will of our people. Syria will defend itself in the face of any aggression," state television quoted Assad as saying.

However Russia and Iran, both Syrian allies, have warned against a military intervention in Syria. Russia has said it is too early to consider any reaction by the United Nations Security Council, of which it is a permanent member with veto power. Moscow said any reaction should wait until the UN team inspecting the attack sites releases its findings.

The UN team returned to the alleged attacks sites Thursday to continue their investigation. UN Secretary General Ban Ki-moon said the team will leave Syria on Saturday.

US prepares for strike

Ban also said he had spoken with US President Barack Obama on Wednesday, as Washington appears to be moving closer to a military strike.

"I... expressed my sincere wish that this investigation team should be allowed to continue their work as mandated by the member states," Ban said.

"We discussed how the UN and the world can work together particularly with the United States, (and) how we can expedite the process of investigation," he added.

"Diplomacy should be given a chance... peace (should) be given a chance," he said.

US President Barack Obama, however, has already spoken of the kind of strike the US would use to deter future chemical weapons use.

Speaking to US public broadcaster PBS on Wednesday Obama said it would be a "tailored, limited" strike rather than a drawn-out military campaign, adding that "direct military engagement, involvement in the civil war in Syria, would not help the situation on the ground."

The US president said he had "not made a decision" on how close he was to approving military intervention, but that such an operation would send a "strong signal" to Assad.

"We have concluded that the Syrian government in fact carried these [attacks] out," Obama said, "and if that's so, then there need to be international consequences."

Military assets reshuffled

The British parliament was to debate a government motion later on Thursday on a possible response to the Syrian regime's alleged gas attack. Prime Minister David Cameron is to use the dabate make the case for military action. However, opposition from within British parliament has already forced Cameron to promise he would wait to launch a military strike until the UN weapons inspectors had presented their findings.

German Chancellor Angela Merkel agreed with Cameron in a phone call Wednesday that there was "sufficient evidence" of Syria's chemical weapons use, making "an international reaction essential."

"Both hope that no member of the [United Nations] Security Council closes their eyes to this crime against humanity and that the appropriate consequences will be agreed to," said Merkel's spokesman, Steffen Seibert.

Britain's Ministry of Defense said it has sent six Royal Air Force Typhoon jets to its Akrotiri base in Cyprus as tensions grow over nearby Syria.

"This is purely a prudent and precautionary measure to ensure the protection of UK interests and the defence of our Sovereign Base Areas at a time of heightened tension in the wider region," the ministry said.

The ministry said the jets would not take part in any direct military action.

It was also reported that Russia would send two ships to the eastern Mediterranean to strengthen its naval presence in the area.

The Interfax news agency quoted a source in the armed forces' general staff as saying an anti-submarine vessel and a missile cruiser would be sent due to the “well-known situation,” - a clear reference to the conflict in Syria. However, the state-run RIA Novosti new agency cited a high-ranking naval official as saying the movement was part of a “planned rotation.”

hc/pfd (Reuters, AFP, AP, dpa)