UN Secretary-General Ban Ki-moon on Wednesday called for a diplomatic solution to the Syrian conflict in a speech here in The Hague.

"Syria is the biggest challenge of war and peace in the world today. The body entrusted with maintaining international peace and security cannot be missing in action," Ban said, referring to the UN Security Council.

A UN team is currently investigating allegations of a suspected chemical weapon attack last Wednesday near Damascus, killing over 300 people. Syria has denied it was behind the attack and challenged the U.S. to present hard proof.

According to Ban, the team had not yet found any valuable information.

"But the team needs time to do its research," he said in the Great Hall of Justice. "Let us say here in the Peace Palace: Give peace a chance, give diplomacy a chance. Stop fighting and start talking."

Ban's comments came as British Prime Minister David Cameron said on Wednesday that Britain would submit a draft resolution to the UN Security Council seeking to authorize "necessary measures" to protect civilians in the wake of alleged chemical weapon attacks.