More than sanctions needed to end North Korean threat: John Kerry

Secretary of State John Kerry says it may take more than sanctions to end North Korea's nuclear weapons threat.

Kerry says the US goal remains the same: A peaceful solution that leads North Korea to disarm.

But he acknowledges that North Korea's isolation makes it hard to use economic levers to advance diplomacy, as the US and its partners did with Iran.

Kerry says, it may take more than sanctions with North Korea "because of its total absence of a legitimate economy." He didn't specify the other options.

Kerry spoke a day after Pyongyang said it has upgraded and restarted all of its atomic fuel plants, meaning it could build increasingly sophisticated nuclear weapons. There is wide speculation the government could soon launch new rocket and nuclear tests.