President Barack Obama's national security adviser said Wednesday North Korea won't be allowed to resume dialogue as long as it keeps key parts of its nuclear weapons program running.

Susan Rice made clear that for now, the Obama administration is more interested in talking with Iran than North Korea.

"We are no more interested in talking for talking's sake with North Korea than we would be with Iran," she said in a speech at Georgetown University.

Her speech, titled "America's Future in Asia," came amid criticism that Obama's strategy of rebalancing toward the region

has been losing momentum. Critics accused the Obama administration of disregarding Pyongyang, claiming it is focusing on Iran and other Middle East issues.

The top national security aide to Obama was giving her first major public speech on Asia since taking office in the summer, apparently seeking to show the administration is still committed to the increasingly important region.

Rice, formerly Washington's ambassador to the United Nations, pointed out North Korea's track record of engaging in dialogue while pursuing its nuclear and missile programs.

"North Korea knows exactly what it needs to do to demonstrate that it's serious," she said with respect to the preconditions for the resumption of six-way talks.

She did not elaborate, but multiple sources say Washington wants Pyongyang to stop enriching uranium, impose a moratorium on nuclear and long-range missiles tests and allow the return of international inspectors to its main nuclear complex in Yongbyon.

Only after North Korea takes such initial steps, "authentic and credible" negotiations with Pyongyang are possible for concrete and irreversible steps toward denuclearization, said Rice.

She stressed Pyongyang's attempts to "engage in dialogue while keeping critical elements of its weapons program running" are not acceptable.

"They will not succeed ... We will maintain and expand as necessary both national and multilateral sanctions against North Korea," she said. Rice reaffirmed that Washington is prepared to restart talks as long as Pyongyang is serious about denuclearization.

In case of further provocations, however, she said North Korea will continue to pay significant costs.

"So Pyongyang has a choice" between greater isolation and development based on global integration, she stressed.

On ties with South Korea, she said Seoul and Washington are enhancing the alliance's military capabilities to ensure that their combined forces can deter and fully answer any North Korean provocations.

Rice also announced Obama's plans to visit Asia in April to make up for the cancellation of trips there last month.

Obama called off planned trips to regional summits in Indonesia and Brunei and stops in the Philippines and Malaysia due to a 16-day government shutdown caused by a budget impasse in Congress.

On China, Rice said the U.S. will stay on a two-track approach -- boosting cooperation on major regional and global issues, while putting pressure on Beijing to level the ground for competition in trade, cyberspace and other areas. (Yonhap News)