U.S. Secretary of State John Kerry demanded Wednesday that Russia force Bashar Assad's government to ground its air force in order to revive hopes of a ceasefire in Syria's civil war.

Addressing the U.N. Security Council, including his Russian opposite number Foreign Minister Sergei Lavrov, Kerry said efforts to find peace could yet be salvaged but only if Moscow takes responsibility for recent airstrikes.

Kerry said that only Russian and Syrian war planes had been active in areas of northern Syria where on Monday a United Nations aid convoy had been destroyed from the air and on Tuesday a field clinic was bombed.

...