"I’m not going to elaborate with any detail on the proposed resolution… there is no question that if the resolution is approved, it will go beyond anything that we have previously passed," Kerry told a joint press conference with Chinese Foreign Minister Wang Yi on Tuesday.
Kerry added that both Washington and Beijing were evaluating the resolution.
"The fact that it has reached a stage of where it is being evaluated is significant," the state secretary added.
In January, Pyongyang declared that it had successfully carried out a hydrogen bomb test, triggering condemnation from the international community. North Korea fired a long-range rocket to allegedly put a satellite into orbit, violating UN Security Council resolutions banning it from launches that may be used as ballistic missile carrying nuclear warheads the following month.