The secretary of state recently returned from a tour of Asia and credits China with being "extremely positive and productive" in respect to North Korea.
The hardline North Korean regime has abandoned promises to dismantle its nuclear program and recently conducted a number of missile tests and an underground nuclear explosion.
She also said that the U.S. and the world's major powers were united in preventing Iran from getting its hands on a nuclear weapon.
"Your (Iran's) pursuit is futile," she said, adding that Iran did not have the right to develop a nuclear weapon.
At the same time she says that Washington remains ready for dialogue with Iran on is nuclear program.
On another front, Clinton is implicitly urging Israel to give U.S. policy on Iran's nuclear ambitions a chance to work.
There are increasing concerns that Israel -- seen as a primary target of an Iranian weapons program -- might launch a first strike to destroy Tehran's nuclear sites before the Islamic regime is able to build a bomb.
Clinton says that Washington hopes the Jewish state understands American attempts to talk to Iran is a better approach.
The Associated Press contributed to this report.