Western powers told the Syrian opposition to expect a strike against President Bashar al-Assad's forces within days, according to sources who attended a meeting between envoys and the Syrian National Coalition in Istanbul.
"The opposition was told in clear terms that action to deter further use of chemical weapons by the Assad regime could come as early as in the next few days, and that they should still prepare for peace talks at Geneva," one of the sources who was at the meeting on Monday told Reuters.
The meeting at a hotel in downtown Istanbul was between senior figures of the Syrian National Coalition, including its president Ahmad Jarba, and envoys from 11 core "Friends of Syria" alliance members, that included U.S. envoy Robert Ford, the top U.S. official handling the Syria file, the sources said.
Facing Russian and Chinese disapproval that could dampen prospects for proposed peace talks in Geneva, Assad's foes have vowed to punish a poison gas attack in some rebel-held districts of Damascus on August 21 that killed hundreds.
U.N. experts trying to establish what exactly happened in the attack were finally able to cross the frontline on Monday to see survivors – despite being shot at in government-held territory. But they put off a second visit until Wednesday.
AFP meanwhile reported that Britain's armed forces are drawing up contingency plans for military action in Syria, according to Prime Minister David Cameron's spokesman, but that no decision had been made about what response may be taken.
Cameron will decide later on Tuesday whether to recall lawmakers from their summer break to debate a possible military intervention in the wake of an alleged chemical weapons attack near Damascus last Wednesday, Downing Street said.
"We are continuing to discuss with our international partners what the right response should be, but, as part of this, we are making contingency plans for the armed forces," Cameron's spokesman said.
The prime minister will continue talks with other world leaders to agree a "proportionate response" to the gas attack, which the United States, Britain and France say was committed by Syrian government forces.
"This is about deterring the use of chemical weapons," the British spokesman said.
