The agreement reached with Russia on Syria is the most far-reaching chemical weapons-removal scheme ever, US Secretary of State John Kerry said Sunday, dpa reported.
But the military option remains on the table if President Bashar al-Assad fails to comply, he warned in Jerusalem.
"Now this will only be as effective as its implementation will be and (US) President (Barack) Obama has made it clear that to accomplish that, the threat of military force remains," he said.
"We cannot have hollow words," he warned, because that would affect other players affecting the international community, including Iran and North Korea.