PARIS (AFP) - US Secretary of State John Kerry said on Sunday that Arab League ministers had agreed at talks in Paris that Syria crossed a "global red line" in its alleged chemical weapons attack.

Mr Kerry said a number of Arab countries were willing to sign a statement agreed by 12 countries of the G20 that called for a reaction to the alleged attack, and that they would make announcements in the next 24 hours.

"All of us agree, not one dissenter, that Assad's deplorable use of chemical weapons... crosses an international global red line," Mr Kerry told journalists after the talks.

"Today we discussed the possible and necessary measures that can be taken," he said.

"A number of countries immediately signed on to the G20 agreement," Mr Kerry said, naming Saudi Arabia as among them.

"I am not going to name the other countries simply because we agreed in the meeting they would go back and make their own announcements, which they will do within the next 24 hours," Mr Kerry said.

"Everybody understood that the decisions need to be made within the next 24 hours."

Mr Kerry met Saudi Foreign Minister Saud al-Faisal, who he said had made clear his country's support for military action.

"They have supported the strike and they have supported taking action," Mr Kerry said.

Qatari Foreign Minister Khaled al-Attiyah said the alleged attacks on Aug 21 saw the regime of Bashar al-Assad move from conventional warfare to "weapons of mass destruction".

"If the international community really wants to protect international peace and security, it cannot afford to stand still while unarmed people are being attacked with these weapons," he said.

"We in Qatar support the statement of the 12 out of the G20," Mr Attiyah said.

"We call on other countries to intervene to protect the Syrian people from what they are being subjected to."

Asked about whether Qatar would directly contribute to military action in Syria, he said: "Qatar is currently studying with its friends and the United Nations what it could provide in order to protect the Syrian people."

Sunday's talks brought together officials from the Arab League, Bahrain, Egypt, Jordan, Kuwait, Morocco, the Palestinians, Qatar, the United Arab Emirates and Saudi Arabia.