US Secretary of State Condoleezza Rice has hinted that North Korea faces possible international sanctions if it flouts a diplomatic effort to halt its nuclear weapons programme.
Dr Rice also delivered subtle rebukes to China for raising the stakes in the standoff with Taiwan and for the communist country's limitations on religious freedom.
"I made the point . . . that I do hope there is an understanding that religious liberties are not a threat to changing societies," she said at a press conference.
Dr Rice said she asked Chinese leaders for more help to bring the North Koreans back to the six-way weapons talks. The Pyongyang regime has said it already has at least one nuclear weapon and has given no indication it is ready to bargain further.
"It goes without saying that to the degree that a nuclear-free Korean peninsula gets more difficult to achieve if the North does not recognise that it needs to do that then of course we'll have to look at other options," Dr Rice said at a press conference.
She said she told Chinese leaders the United States is unhappy with the recent passage of a law codifying China's intent to use military force if Taiwan formally breaks away.
The law, she said, "was not a welcome development because anything that increases tensions . . . is not good".
She reiterated US opposition to the potential lifting of an international arms embargo on China - a move the European Union seemed sure to take before the recent escalation of tensions with Taiwan.