The United States and Russia failed on Friday to reach a breakthrough deal on military cooperation and a nationwide cessation of hostilities in Syria, saying they still have issues to resolve before an agreement could be announced.

U.S. Secretary of State John Kerry and Russian Foreign Minister Sergey Lavrov, addressing a joint news conference after more than nine hours of off-and-on talks in Geneva, said teams from both sides would try to finalize details in coming days in the Swiss city.

Kerry said the talks with Lavrov had "achieved clarity on the path forward" but together they offered few details on how they planned to renew a February cessation of hostilities and improve humanitarian assistance.