US President George W Bush said on Monday that he hoped Washington's partners in North Korean nuclear disarmament talks will stay "firm and patient" with the secretive regime.
Fresh talks last week failed to yield a formal verification mechanism for ensuring North Korea tells the truth about its nuclear programmes, after the communist state refused to sign up to a Chinese drafted proposal.
"The key is to be firm and patient with a structure that will enable the next president, or the next president after that, to be able to solve the problem diplomatically," Bush told reporters on board his official Air Force One airpline.
He was speaking between surprise visits to Iraq and Afghanistan, his last before he leaves the White House next month.
"Right now, what you're watching is that the leader of North Korea is trying to test the process," Bush said, referring to the diplomatic efforts grouping China, Japan, Russia, North and South Korea, and the United States.
"The objective is to keep our partners firm on the understanding that the six party process is the best way to solve the North Korean issue," said Bush, who underlined "we need to have a verifiable process" of denuclearization.
"In the old process it used to be 'we will give you what you asked for and hope that you'll respond.' Now it is 'here's what you must do if you want our help,'" he said.
North Korea agreed to give up its nuclear programmes in return for energy aid and diplomatic concessions under a deal worked out by the six nation talks negotiators.
Washington said after the talks collapsed last week that shipments of fuel would be suspended, but Pyongyang responded by threatening to slow down work aimed at dismantling its nuclear facilities.