U.S. nuclear envoy Christopher Hill said Monday a stalled process to shut down Pyongyang's nuclear program could resume within weeks now that a dispute over the transfer of North Korean funds is over.

But Hill, who arrived in Beijing for talks Monday, said there was still a lot of work to do to get the process back on track after it was stalled for months by a dispute over the transfer of frozen North Korean funds.

North Korea over the weekend invited inspectors from the International Atomic Energy Agency to visit as the transfer of the money appeared to be complete.

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"Political will is something we are going to need, but from the technical point of view I think all of it is quite doable," Hill told a news conference after a less than 10-hour stop in Beijing.

"Our sense is that it will be down to a matter of weeks, not months," Hill said about restarting the process.

He said North Korea had to close and seal its Yongbyon reactor, and IAEA inspectors had to monitor that.

In Vienna, IAEA spokeswoman Melissa Fleming confirmed the North Korea invitation had been received and said the "next steps" would be discussed on Monday.

North Korea said a "working-level delegation" from the U.N. nuclear watchdog had been invited to discuss procedures for the verification and monitoring of the reactor's shutdown. North Korea expelled IAEA inspectors in December 2002.

Hill met his Chinese counterpart Wu Dawei to discuss when the next round of six-party talks can be held. He has already said they are likely in early July.

It was "a good opportunity to review with the Chinese hosts of the six-party process where we are in the process," Hill said.

He did not give any other details of the talks.

Hill said the participants in six-nation talks on North Korea's nuclear disarmament — the U.S., host China, Russia, Japan and the two Korea — should now move to fully implement a February agreement.

North Korea had refused to move on its February pledge to shut down the Yongbyon reactor until it receives about $25 million in funds that were frozen in a Macau bank. The U.S. accused Banco Delta Asia of helping North Korea's government pass fake $100 bills and launder money from weapons sales.

Claiming the financial freeze was a sign of Washington's hostility, North Korea boycotted the six-nation talks for more than a year, during which it conducted its first-ever atomic bomb test last October.

Russia's Interfax news agency, citing an unnamed North Korean official, reported Monday that North Korea plans to shut down Yongbyon in the second half of July.

"Based on our specialists' evaluations, it will take one month to technically shut down the reactor. This way, we expect to seal it in accordance with agreements reached at six-party talks in the second half of July 2007," the official was quoted as saying.

South Korea plans to start shipping 50,000 tons of heavy fuel oil to North Korea by the time it shuts down its nuclear reactor, South Korean chief nuclear envoy Chun Yung-woo has said, adding preparations could begin in the coming weeks.

The North is to eventually receive further energy or other aid equivalent to 950,000 tons of heavy fuel oil in return for irreversibly disabling the reactor and declaring all nuclear programs.

Complete coverage is available in FOXNews.com's North Korea Center.