SEOUL, South Korea – North Korea pledged Wednesday to detail its nuclear programs and disable all activities at its main reactor complex by the end of the year, its firmest commitment to disarm after decades seeking to develop the world’s deadliest weapons.

The agreement at talks in China came on the same day North Korean leader Kim Jong Il held talks in the communist nation’s capital of Pyongyang with South Korean President Roh Moo-hyun at the first summit between the two countries in seven years.

In Washington, President Bush hailed the nuclear deal and said it reflected the “common commitment” of the talks to shut down North Korea’s atomic weapons program.

Under an agreement reached in February, Pyongyang was required to shut down and seal its sole operating reactor at its main nuclear complex, which it did in July after the U.S. reversed its hard-line policy against the regime. The second phase required it to disable the reactor and provide a full description of all its nuclear programs. Wednesday’s agreement calls for that to happen by the end of the year.

The North said it would allow the U.S. to lead experts to Pyongyang within two weeks “to prepare for disablement” of its nuclear facilities, Chinese Vice Foreign Minister Wu Dawei said in Beijing.

The U.S. has agreed to lead disablement activities and provide the initial funding for them. Washington also reiterated its willingness to remove North Korea from a list of countries that sponsor terrorism.

No timetable was set for this action, but a joint statement said it will happen “in parallel with” the North Korean government following through on its commitment.

“The two sides will increase bilateral exchanges and enhance mutual trust,” the statement says.

Besides the U.S. and China, three other countries – Russia, South Korea and Japan – participated in the talks with the North.

The five countries reiterated a commitment to deliver aid under the February disarmament deal granting the North the equivalent of 1 million tons of fuel oil. On Friday, in anticipation of the new agreement, the United States also announced it would spend up to $25 million to pay for 50,000 tons of oil for North Korea.

Associated Press writers Jae-soon Chang, Kwang-tae Kim, Hyung-jin Kim, Audra Ang and Jennifer Loven contributed to this report