"I am hopeful and we will keep working on it," Kerry, who is leading the US effort to push the two sides toward a deal, said during remarks at the Munich security conference.
The Obama administration hopes to complete a 'framework' accord in coming weeks, and will then seek to negotiate a final peace deal by the end of 2014, a US offical said this week.
Kerry also said the United States was not being "quixotic" in the effort.