ISTANBUL (Reuters) - An international peace conference on Syria, planned to be held in Geneva, is off the table for now following an alleged chemical weapons attack in Damascus, a senior member of Syria's opposition coalition said on Monday.

Members of the Syrian National Coalition met representatives of the "Friends of Syria", a group of Western and Arab nations opposed to President Bashar al-Assad, in Istanbul on Monday in a meeting originally meant to discuss plans for the conference.

"It (the meeting) was for Geneva but we refused to speak about Geneva after what's happened ... We must punish this dictator, Bashar the Chemist we call him, and then we can discuss Geneva," coalition Secretary General Badr Jamous told Reuters after the meeting.

Syria's opposition accused government forces of gassing hundreds of people by firing rockets that released deadly fumes over rebel-held Damascus suburbs on August 21, killing men, women and children as they slept.

(Reporting by Dasha Afanasieva; Writing by Nick Tattersall)