The Bush administration said Wednesday it will not accept a North Korean nuclear declaration that does not fulfill Pyongyang's obligations under the six-party disarmament accord. U.S. intelligence officials are preparing to brief congressional leaders on North Korean proliferation activity. VOA's David Gollust reports from the State Department.

Officials here are underscoring the administration's firm line on the declaration in advance of a briefing on Pyongyang's proliferation activity that could harden congressional opposition to the six-party accord.

Pyongyang is more than three months overdue in making a full declaration of its nuclear program, including any proliferation activity, under the Chinese-sponsored six-party accord, in which it is to scrap its program in exchange for aid and diplomatic benefits.

News accounts say U.S. intelligence officials will brief key members of Congress Thursday on what the United States knows about North Korean proliferation, including a nuclear site Pyongyang was building for Syria that was reportedly bombed by Israel last September.

Senior U.S. and North Korean diplomats were said to have reached an understanding in Singapore earlier this month under which Pyongyang would declare its physical nuclear assets, including 30 kilograms of bomb-grade plutonium, but only tacitly admit involvement in proliferation.

But in a talk with reporters Wednesday, State Department Spokesman Sean McCormack said nothing was finalized in Singapore, as evidenced by the administration's dispatch of senior State Department Korea expert Sung Kim to Pyongyang this week for more talks on the declaration.

McCormack said ending the North Korean nuclear program, which included a weapons test in 2006, is a "compelling" U.S. national security interest. But he said the Bush administration won't accept a North Korean declaration that is inconsistent with the six-party accord:

Sung Kim talks to reporters upon arrival at Incheon International Airport, S. Korea, 21 Apr 2008

"Our view was that there was more work to do, as evidenced by Sung Kim's travel to Pyongyang, and we'll see what the North Koreans come up with," he said. "The onus is on them to come up with a declaration that satisfies the other members of the six-party talks. If it doesn't, we're not going to accept some declaration that we don't feel is consistent with their obligations."

McCormack said Sung Kim, a Korean-American who heads the State Department's office of Korean affairs, is expected to leave Pyongyang Thursday after two days of meetings on the declaration.

Conservative critics of the administration's approach to North Korea have pointed to alleged North Korean nuclear help for Syria as grounds for opposing the six-party deal.

Spokesman McCormack said the pending intelligence briefing is unlikely to change the opinion of the six party accord's most ardent critics.

Among them is former Bush administration U.N. ambassador John Bolton, who wrote last week that the administration's handling of the declaration amounts to "surrender" to Pyongyang.