UN Secretary-General Ban Ki-moon today warned that any "punitive" action taken against Syria for an alleged chemical weapons attack would be illegal without the backing of Security Council and any military action against the country may unleash more turmoil.

Ban called for handling any action against the Syrian regime within the framework of the United Nations charter.

"For any course of actions in the future, depending upon the outcome of a scientific analysis will have to be considered by the Security Council for any action, and that's my appeal, that everything should be handled within the framework of the United Nations charter," Ban told UN reporters during a news conference.

"The use of force is lawful only when -- in exercise of self- defence in accordance with Article 51 of the United Nations charter, and/or when the Security Council approves such action. That is the principle of the United Nations," he said in response to a question.

"If confirmed, any use of chemical weapons by anyone under any circumstances will be a serious violation of international law and outrageous war crime," Ban told reporters at a news conference at the UN headquarters in New York.