International mediator Lakhdar Brahimi said in Geneva on Saturday the first two rounds of peace talks had not made much progress but the two sides had agreed on an agenda for a third round at an unspecified date.
Speaking during a trip to Asia and the Middle East, Mr Kerry said: "The regime stonewalled. They did nothing except continue to drop barrel bombs on their own people and continue to destroy their own country. And I regret to say they are doing so with increased support from Iran, from Hezbollah and from Russia."
Mr Kerry appears to be trying to tighten diplomatic pressure on President Bashar al-Assad and reach a political settlement that can end government attacks on rebel-held areas and find a solution for tens of thousands of Syrians cut off from humanitarian assistance.
Using unusually strong language, Mr Kerry said: "Russia need to be a part of the solution and not be contributing so many more weapons and so much more aid that they are in effect enabling Assad to double-down, which is creating an enormous problem."
He said Mr Assad is still trying to win Syria's civil war militarily rather than find a solution through peace talks.
Russia has said the peace talks must not focus only on a transitional governing body.