Speaking briefly to reporters after meeting with Israeli Prime Minister Binyamin Netanyahu, Kerry said "diplomacy has been the preferred path for the president of the United States, and I think it is any peace loving nation's choice. But make no mistake, we have taken no option off the table."
Kerry arrived in Jerusalem to brief Netanyahu about the Geneva agreement with Russia over the fate of Syria's chemical weapons stockpile.
He warned if Syria fails to implement the agreement, President Barack Obama made it "absolutely clear about the reminder of the potential use of force," The Jerusalem Post quoted him saying.
Israel is following developments in Syria closely, the newspaper said Netanyahu said. The situation has shown "something that I have been saying for quite some time: that if diplomacy has any chance to work it must be coupled with a credible military threat, What is true of Syria, is true of Iran, and by the way, vice-versa."
Earlier, Israel's Channel 2 said Kerry's meeting would focus not only on developments in Syria but also on the Israeli-Palestinian peace process.