Speaking to the BBC ahead of an Asian tour, Mrs Clinton said North Korea's nuclear plans, the economic crisis and climate change would top the agenda.

She warned North Korea against "provocative action" but stressed the wide range of incentives for Pyongyang to give up its nuclear programme.

Her week-long tour will take in Japan, China, South Korea and Indonesia.

The stops reflect the diversity of ties the US has in the region, BBC state department correspondent Kim Ghattas in Washington says.

"Going to Asia signals that the US is not just a transatlantic power but also a transpacific power," Mrs Clinton told the BBC.

"We are looking to create partnerships and opportunities for co-operation that we believe are in our national security interests and in keeping with our values."

She also stressed that the US was keen to work more collaboratively with China.

While some saw China as an adversary, Mrs Clinton said, there were real opportunities to develop a good relationship with Beijing on issues such as climate change and clean energy.

Mrs Clinton went on: "There is a pent-up desire

on the part of the United States government under the Obama administration, as well as partners around the world, that we begin to work together to solve a lot of our common problems...

"On climate change, pandemic prevention, nuclear proliferation, on all of these serious threats and challenges that we face, we are going to assume a leading role again."

Stalled talks

Ties between the two countries have in the past focused on the economy, our correspondent says, but Mrs Clinton and the state department now seem to be taking the lead in managing that relationship.

It is the first time in 60 years that a secretary of state has made Asia the destination of a first trip in office, our correspondent adds.

Earlier, giving her first big foreign policy speech at New York's Asia Society, Mrs Clinton urged North Korea not to take any "provocative action" that would undermine talks on the issue.

Her trip to Asia comes amid speculation in regional media outlets that North Korea may be preparing for a long-range missile test.

Mrs Clinton described the country's nuclear programme as "the most

acute challenge to stability in north-east Asia" and said the nations involved in six-party talks on the issue would need to work together to make progress.

She made clear that the US would hold Pyongyang to its commitment to give up its nuclear programme in return for diplomatic concessions and economic aid.

"If North Korea is genuinely prepared to completely and verifiably eliminate their nuclear weapons programme, the Obama administration will be willing to normalise bilateral relations", she said.

Mrs Clinton added that the US would also be prepared "to replace the peninsula's long-standing armistice agreements with a permanent peace treaty, and assist in meeting the energy and other economic needs of the North Korean people".

The six-party talks, involving the US, China, Russia, Japan and South Korea, as well as North Korea, have been stalled for months.

The US has concerns about how to verify Pyongyang's past nuclear activities and wants North Korea to disclose its full nuclear arsenal. Pyongyang, meanwhile, says it is not receiving the aid promised in the 2007 aid-for-disarmament deal.