World Leaders Agree on Steps to Revive Syria Truce Amid Escalating Violence

LONDON— -- World powers tried to revive a shaky ceasefire in Syria today when U.S. Secretary of State John Kerry and Russian foreign minister Sergei Lavrov co-chaired a meeting of the International Syria Support Group in Vienna.

“Those involved in this conflict with competing agendas are going to have to be willing to prioritize peace,” Kerry said after the meeting.

The International Syria Support Group (ISSG) agreed today to work on “transforming hostilities into a comprehensive ceasefire” and increase pressure on the parties in the conflict to comply.

Those who persistently break the truce can be excluded from it, Kerry said.

Meanwhile, the delivery of humanitarian assistance will begin or resume in more than a dozen Syrian areas, including Douma, Darayya, Yarmouk, Zamalka, Harasta and Madaya, which are isolated from the outside world. June 1 is the deadline for delivering the aid.

“If the U.N. is denied humanitarian access to any of these areas, the ISSG calls on the World Food Program to immediately carry out a program for air bridges and airdrops for all those areas in need,” Kerry said. “The ISSG pledges to support such program and also calls on all parties to provide a secure environment for that program.”

Kerry also said that the group will intensify efforts to stop bombings of areas in Syria with a high number of civilians and that Russia will work with the Syrian authorities in an attempt to put an end to government bombardments in predominantly civilian areas. He stressed that the Syrian conflict has gone on for too long and that the stakes are high.

"None of us, not one can be remotely satisfied with the situation in Syria," he said. "It's deeply disturbing and we're all concerned about the levels of violence that broke out in recent days."

The ISSG has set an Aug. 1 deadline for the formation of a transitional, non-sectarian government in Syria, which is supposed to lead to elections within 18 months, but Kerry said the “August date is a target date,” not a firm deadline.

In February, the United and Russia mediated a ceasefire in Syria, which reduced fighting, but violence has escalated recently.

Today’s meeting in Vienna was initiated after U.N. Syria envoy Staffan de Mistura appealed last month to the United and Russia to help resuscitate the Syria peace talks.