WASHINGTON (CNN) -- North Korea delivered a verbal response Friday to a letter President Bush sent to North Korean leader Kim Jong Il earlier this month about the progress of nuclear talks, officials said.
Kim Jong Il's North Korea has until December 31 to hand over a document declaring its nuclear secrets.
Details of the response were not immediately released but senior State Department officials said the gist was that North Korea plans to hold up its end of the bargain and expects the United States to do the same.
Bush's letter indicated six-party talks aimed at denuclearization of the Korean peninsula were at a "critical juncture."
It urged Pyongyang to follow through on an agreement to declare and dismantle its nuclear program, according to State Department deputy spokesman Tom Casey.
Casey said the Bush letter, dated December 1 and addressed to "Mr. Chairman," was intended to show the United States is serious about keeping the process moving. Bush wrote similar letters to Russia, China, South Korea and Japan, its negotiating partners.
"I got his attention with a letter," Bush told reporters Friday, referring to Kim. "And he can get my attention by fully disclosing his programs, including any plutonium he may have processed and converted. ... We just need to know. As well, he can get our attention by fully disclosing his proliferation activities."
North Korea is facing a December 31 deadline to hand over a document declaring its past and present nuclear secrets.
However, chief U.S. negotiator Christopher Hill, who hand-delivered Bush's letter, said differences remain over what should go into that document, and it is unclear how "full and complete" it should actually be.
Hill also said he believes the disablement is "going well." E-mail to a friend
CNN's Elise Labott and Suzanne Malveaux contributed to this report