NEW YORK (Reuters) - The United States' envoy for North Korea said on Monday that Pyongyang's recent actions over its nuclear program were part of the "rough and tumble" of hard disarmament negotiations.
Envoy Christopher Hill also raised whether the reported ill-health of North Korea's leader Kim Jong-il had led to the tougher line taken by Pyongyang in the past month, including a vow to restart its Yongbyon nuclear facility.
"We have had a difficult time in the past month," Hill told reporters of recent actions by North Korea that appear aimed at reversing a nuclear disarmament deal.
"Now this corresponds, of course, to, I think, the widely reported issues involving the health of the leadership there. How much it relates to that is hard to tell at this point but we feel we need to keep our focus on the verification protocol," he said.
North Korea has rejected reports that Kim is ill. U.S. intelligence officials have said it is possible the North Korean leader suffered a debilitating stroke and this was why he had not been seen in public for the past month.
"Clearly we are seeing a tough line in the last month from them," said Hill, adding the United States was still in close contact with North Korea via its New York diplomatic channel.
Earlier on Monday, North Korea asked the U.N.'s nuclear watchdog to remove seals and cameras from its main atomic complex, Yongbyon, after vowing to restart the facility -- effectively reversing a nuclear disarmament deal with the United States, China, Russia, Japan and South Korea.
A senior diplomat close to the International Atomic Energy Agency said seals had since been removed but did not elaborate. An IAEA official could not confirm that development and said efforts were being made to clarify the situation.
Hill too said he could not confirm that the seals had been removed.
He said North Korea's recent actions came at a tough time in the negotiating process as efforts were intensified to get Pyongyang to agree to a mechanism to verify their nuclear claims.
"We are in a degree of detail which we haven't had before. The more you go into these six-party issues, the more difficult it gets. But we have been able to get through tough spots before and let's see if we can get through this one," he told reporters.
"I would rather you think of this as a very rough and tumble moment in the negotiation process," he said.
Hill said he was consulting with other members of the six-party talks to decide how to proceed.
U.S. Secretary of State Condoleezza Rice was set to have dinner on Monday with China's foreign minister, and North Korea's nuclear program was the key issue on the table. Earlier she met South Korea's foreign minister on the sidelines of the U.N. general assembly.
North Korea said on Friday it was working to reactivate the plutonium-producing Yongbyon complex, the basis of its atomic bomb program it had been dismantling since last November under a disarmament-for-aid deal.
Hill said any restarting of the reprocessing facility at Yongbyon would require extensive testing and this could take months.
"I don't think there is any immediate potential for restarting the thing but obviously these reports are ones that we take very seriously," he said.
(Editing by Philip Barbara)