WASHINGTON (REUTERS) - US foreign policy and North Korea experts said in a report released on Wednesday that the United States should engage more with North Korea as a way to revive talks aimed at ending Pyongyang's nuclear-weapons program.

The joint report from two think tanks, National Security Network and the National Committee on North Korea, said Washington needs to shift from an "all or nothing" approach requiring Pyongyang to meet conditions for the resumption of nuclear talks with major powers that were suspended in 2009.

The current approach, in which US-North Korean contact generally has been limited to a channel via the North Korean mission at the United Nations, effectively gave the initiative to Pyongyang when Washington should be aiming to set the agenda, the report argued.

"The refusal to engage in any preliminary measures will inevitably lead to a de-facto acquiescence to North Korea's nuclear status," it said. "Interim steps can provide immediate value to the United States while also putting more concrete steps towards denuclearization into the real of the possible."

North Korea promised to abandon its nuclear program in 2005 but backed away from the agreement, testing nuclear devices in 2006 and 2009. Talks among North Korea, South Korea, Japan, China, Russia, and the United States began in 2003 with the goal of denuclearising the Korean peninsula but were suspended after North Korea launched a ballistic missile.

The experts' report urged an effort by the United States and other countries to increase contact with North Korean officials in order to build working relationships.

It said the Obama administration should identify a prominent high-ranking government official who could secure high-level meetings in North Korea.

The process could begin, it said, with an expansion of low-key engagement in humanitarian, educational and environmental issues with North Korea, something South Korea, a key US ally and Pyongyang's arch rival, was already engaged in.

A modest first step to broaden mutual understanding would be for the United States to issue visas to North Koreans not involved in security or other sensitive areas.

The report also called for a resumption of US-North Korean missions to search for the remains of US personnel missing from the Korean War as a way to build direct relations between the armed forces of both countries.

"Preventing escalations during flareups ... hinges on developing a better understanding between respective military leaders," the report said, adding that the approach paid off in normalising post-war relations with Vietnam.

More than 8,100 US service members remain missing from the 1950-53 war, but in 2005 the Pentagon suspended US efforts inside North Korea to find remains. It accused Pyongyang of creating an atmosphere dangerous to US workers.

The report urged Washington to support South Korea's proposal to establish the North-east Asian Peace and Security Initiative, a multilateral forum that would include North Korea and enable dialogue beginning with regional "soft issues," such as the environment, disaster relief and nuclear safety.

Mr Christopher Hill, a former US assistant secretary of state who headed the US-North Korea nuclear talks, said failing to engage with North Korea was counterproductive.

"Outrage is not a policy," he said, referring to US critics of North Korea opposed to engagement. "The more you talk to these people, the more they become acquainted with reality."

Mr Hill said that while the North Koreans were not in a position to threaten the United States with nuclear weapons, it did not mean the intent was not there.

"To ignore it or not to put together a process to deal with it is not going to make the problem go away. The problem will eventually be there for us," he said.

Mr John Bradshaw, executive director of the National Security Network, said the report would be circulated on Capitol Hill and shared with the US state and defence departments.

"What are the alternatives? Doing nothing leaves you with the same situation or worse in several years," he said.

US Representative Eliot Engel, the senior Democrat on the House Foreign Affairs Committee, said after the report's release that the United States needed to remain committed to the goal of denuclearising North Korea, "despite the many setbacks that have halted progress."

"We should not give up on diplomacy, because that would mean tacit acceptance of a nuclear North Korea," he said.