By David Brunnstrom

WASHINGTON (Reuters) - The U.S. policy of trying to persuade North Korea to give up its nuclear weapons "is probably a lost cause" and the best that could be hoped for is a cap on the country's nuclear capability, the Director of U.S. National Intelligence James Clapper said on Tuesday.

However, underscoring conflicting views in the Obama administration, the State Department said U.S. policy was unchanged and continued to be to seek the "verifiable denuclearization" of the Korean peninsula.

President Barack Obama has repeatedly stated that the United States will never accept North Korean as a nuclear-armed state.

Clapper made clear at an event at the Council on Foreign Relations think tank in New York he did not think that the policy the administration has stuck to, in spite of repeated North Korean nuclear tests, was realistic.

"I think the notion of getting the North Koreans to denuclearize is probably a lost cause," Clapper said at the Council on Foreign Relations think tank in New York. "They are not going to do that - that is their ticket to survival."

Pyongyang has persisted with its missile and nuclear weapons programs, including a Sept. 9 nuclear explosion, despite strong international sanctions.

Clapper said he got a good taste of how the world looks from North Korea's viewpoint when he went to Pyongyang on a mission in 2014 to secure the release of two Americans.

"They are under siege and they are very paranoid, so the notion of giving up their nuclear capability, whatever it is, is a non-starter with them," he said.

"The best we could probably hope for is some sort of a cap, but they are not going to do that just because we ask them. There's going to have to be some significant inducements."

CHINA PRESSES NEED TO TALK

U.S. State Department spokesman John Kirby said he had not seen Clapper's remarks but told a regular news briefing in Washington that the administration did not believe denuclearization was a lost cause.

"No, nothing's changed ... that's not our position. Our policy objective is to seek to obtain a verifiable denuclearization of the Korean peninsula. That is the policy; that is both the goal and what we want to see and there is a way to do that."

Chinese Foreign Ministry spokesman Lu Kang, asked on Wednesday about Clapper's remarks, said the best way to resolve the North Korea nuclear issue was still via talks.

China and Russia have pushed for a resumption of six-party talks on denuclearization in North Korea. The talks, which also involve Japan, South Korea and the United States, have been on hold since 2008.

Clapper also said it bothered him that the United States was not capitalizing on using information as a weapon against North Korea.

"That's something they worry about a lot ... That is a great vulnerability I don't think we have exploited. Right now, we are kind of stuck on our narrative and they are kind of stuck on theirs."

Clapper was asked if he thought North Korea could mount a nuclear warhead on a missile that could reach the West Coast of the United States and reiterated the intelligence assessment that this had to be a "worst-case assumption."

He said North Korea had yet to test its KN08 intercontinental ballistic missile, so neither North Korea nor the United States knew whether it worked.

"Nevertheless, we ascribe to them the capability to launch a missile that would have a weapon on it to reach parts of the United States, certainly including Alaska and Hawaii," he said.

"They could do it. We have to make the worst-case assumption here."

(Reporting by David Brunnstrom, Eric Walsh and David Alexander; Additional reporting by Ben Blanchard in Beijing; Editing by James Dalgleish, Cynthia Osterman and Nick Macfie)