Arab League foreign ministers on Sunday urged the United Nations and the international community to take "deterrent" action against the Syrian regime over alleged chemical attacks near Damascus.

But they fell short of calling for military strikes as proposed by the United States, amid divisions in Arab ranks with several countries opposed to foreign intervention in Syria.

"The United Nations and the international community are called upon to assume their responsibilities in line with the UN Charter and international law by taking the necessary deterrent measures" following the August 21 suspected chemical attacks, they said in a statement.

The ministers, meeting in Cairo, said the Syrian regime was "responsible" for the attacks which the United States says killed hundreds of people with the use of sarin gas.

US President Barack Obama said he will seek congressional approval to launch a punitive strike on the regime in Damascus over last month's attacks in suburbs of the Syrian capital.

UN chemical weapons inspectors have carried out a probe in the suspected sites and collected samples which will be sent to European laboratories from Monday.

The UN has refused to announce its timeline for finishing the analysis.

"We have learned through samples that were provided to the United States and that have now been tested from first responders in East Damascus, (that) hair samples and blood samples have tested positive for signatures of sarin," US Secretary of State John Kerry told NBC's Meet the Press on Sunday.

The Arab foreign ministers said those responsible for unleashing the poison gas in Syria must be tried before an international court "like other war criminals."

They also called for "all forms of support needed by the Syrian people" but without explicitly calling for military strikes as proposed by the United States and France.