Chief U.N. nuclear inspector Mohamed ElBaradei expressed hope Sunday that his trip to North Korea would help nudge Pyongyang toward nuclear disarmament, but described it as only "the first step in a long journey."

ElBaradei, head of the Vienna-based International Atomic Energy Agency, did not specify whom he would meet in Pyongyang and in Beijing. China was instrumental in clinching the Feb. 13 six-nation agreement under which North Korea agreed to ultimately give up its nuclear arsenal in exchange for economic and political concessions.

An IAEA official, who asked for anonymity because details of the trip were confidential, said meetings still were not finalized.

"Important is not whom we meet but that we progress," ElBaradei told reporters less than an hour before setting out for Beijing en route to Pyongyang for a two-day visit starting Tuesday.

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"I should caution that this is a first step in a long process," ElBaradei said. "This would have to be an incremental process."

Under the Feb. 13 agreement, the first phase of North Korea's disarmament process calls on the country to shut down its main nuclear reactor and allow U.N. inspectors back into the country within 60 days. In return, it would receive aid equal to 50,000 tons of heavy fuel oil from the other countries participating in the six-party nuclear talks — the United States, South Korea, Russia, China and Japan.

U.S. Assistant Secretary of State Christopher Hill, the top American negotiator, said last week that the 60-day schedule was being kept "so far."

In the next phase, North Korea will be required to make a complete declaration to the IAEA and the six parties about its nuclear program, which will then be dismantled.

ElBaradei, whose inspectors were expelled more than four years ago as the North Korean nuclear crisis escalated, said he hoped to "focus on how to bring ... [North Korea] closer to the agency" as well as working on implementing all of last month's agreement.

"As a result of the six party talks ... we are now in a ... much more positive environment," ElBaradei said. "I'd like to see that positive environment translated into positive action."

Experts estimate the reactor at Yongbyon has produced more than 100 pounds of plutonium, which Washington believes has been used to make weapons. Hill last week also said North Korea needs to "come clean" and ultimately abandon what apparently was meant to be a program to enrich uranium — the alternate pathway to nuclear arms.

U.S. allegations that North Korea has a uranium enrichment program brought on the nuclear crisis in 2002 that led the Pyongyang to kick out ElBaradei's inspectors and ultimately contributed to North Korea testing its first nuclear bomb last year. North Korea has never publicly acknowledged that it has such a program.

The United States has had no diplomatic relations with North Korea since the country was created after World War II, when Korea was split into a communist-dominated North and a U.S.-backed capitalist South. North Korea and South Korea remain technically at war, because the armistice has never been replaced by a peace treaty.

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