Senior officials from Japan, the United States and South Korea have agreed to step up pressure on North Korea as they stick to their goal of persuading the communist state to abandon its nuclear weapons.

Their pledge Thursday in Tokyo comes just two days after U.S. National Intelligence Director James Clapper publicly called that goal a "lost cause." He said the best hope is capping its capability instead.

The deputy foreign ministers meeting in Tokyo on Thursday made clear that North Korea now poses a new level of threat and requires broader international pressure and tougher sanctions.

U.S. Deputy Secretary of State Antony Blinken, after meeting with his Japanese and South Korean counterparts, says: "We will not accept North Korea's possession of nuclear weapons, period."