U.S. President George W. Bush and South Korean President Roh Moo-hyun urged North Korea on Friday to return to talks on its nuclear weapons program and played down differences in their approaches to the problem, Reuters reported. "Today's meeting should make it clear that South Korea and the United States are of one voice on this very important issue," Bush told reporters, with Roh seated at his side. During their Oval Office session, Roh gave the president what Bush called a "frank assessment" of the situation on the Korean Peninsula. North Korea is hinting at returning to the six-party negotiations it walked away from a year ago. At the same time, it is boasting of possessing a nuclear arsenal and saying it will build more atomic weapons. There have been fears North Korea will conduct a nuclear test. Roh, in his fourth meeting with Bush, said the United States and South Korea agreed on the basics on dealing with North Korea but hinted the two governments do have differences. --More 0006 Local Time 2106 GMT