The White House said that North Korea must first improve relations with South Korea in order for the six-party nuclear talks to be resumed.

President Barack Obama met with Chinese Prime Minister Wen Jiabao on the sidelines of the U.N. General Assembly in New York.

In a briefing after the bilateral, Jeffrey Bader, senior director for Asian Affairs at the U.S. National Security Council, said the two leaders did not discuss North Korea.

But he said the U.S. expects to see the North "take steps to address the grievances of South Korea in the wake of the South's sunken warship." Bader said this is a critical first step before there can be any sort of multilateral process. He said Washington would then want to see "some kind of behavior or manifestations by the North that indicate a sincerity about denuclearization."