President George W. Bush urged North Korea leader Kim Jong-il on Wednesday to return to stalled six-party talks on its nuclear program "for the sake of peace and tranquility and stability." Bush, at a news conference with Mexican President Vicente Fox and Canadian Prime Minister Paul Martin, denied setting a June deadline for North Korea to return to talks and said the five nations that have been negotiating with Pyongyang -- the United States, China, Japan, South Korea and Russia -- were united. "I'm a patient person. And so are a lot of people that are involved in this issue. But the leader of North Korea must understand that when we five nations speak, we mean what we say," Bush said. Bush said he received a two-hour briefing from Secretary of State Condoleezza Rice about her recent trip to Asia. He said Chinese President Hu Jintao made clear to Rice that it was still the objective of the Chinese government to pursue six-party negotiations. There have been suggestions from the Chinese in the past that the United States must talk directly to North Korea. --More 2239 Local Time 1939 GMT