Secretary of State Condoleezza Rice (search) said Monday night the United States reserves the right to seek U.N. Security Council action on North Korea but remains committed for the time being to seeking a negotiated end to the country's nuclear weapons program.

"We still believe there is a lot to be done within the six-party framework," Rice said, alluding to disarmament negotiations that began almost two years ago. There have been no talks since June 2004 because of North Korea's unwillingness to renew the discussions.

Rice spoke to reporters while en route to Brazil, the first stop on a four-country Latin American tour.

A decision on whether to seek Security Council action will depend on "the nature of the threat" North Korea (search) poses and the views of other members of the six-party process, Rice said. Besides North Korea and the United States, other participants are China, South Korea, Japan and Russia.

Rice declined to say how long she would give North Korea to return to the negotiating table. Referral to the Security Council (search) could mean the imposition of sanctions against the communist state.

Rice appeared to reject a report suggesting the Bush administration may seek a Security Council resolution authorizing all nations to intercept shipments of goods in and out of North Korea that may contain nuclear material.

She said the United States is already capable of dealing with proliferation issues involving North Korea or other countries through an international program that allows for the boarding of suspect vessels on the high seas.

The Proliferation Security Initiative has already carried out "a couple of very major operations that have yielded both information and cargo that was associated with weapons of mass destruction or WMD technology," Rice said.

She said the initiative is based on existing international law and does not require Security Council resolutions.