Pyongyang's agreement to suspend its nuclear program in exchange for nutrition aid from the United States sends a positive signal, but difficulties in solving nuclear issues on Korean Peninsula remain, analysts say.

Through the agreement, both the United States and the Democratic People's Republic of Korea expressed a sound willingness to improve bilateral ties, said Wang Junsheng, an expert on Asia-Pacific studies with the Chinese Academy of Social Sciences.

China welcomed the improvement of Washington-Pyongyang ties and their contribution to maintaining peace and stability on the Korean Peninsula, the Chinese Foreign Ministry said on Thursday.

"China appreciates that the US and the DPRK reaffirmed to implement the 9/19 Joint Statement, and would take positive measures related," said Foreign Ministry spokesman Hong Lei.

"China is willing to work with relevant parties to continue to push forward the Six-Party Talks process, and play a constructive role to realize long-term peace and stability on the Korean Peninsula and Northeast Asia."

Huang Youfu, an expert on Korean studies with the Minzu University of China, said that the agreement has created a good foundation for the resumption of the Six-Party Talks.

The DPRK agreed to halt its nuclear tests, long-range missile launches and uranium enrichment activity at Yongbyon, Pyongyang's Korean Central News Agency said on late Wednesday.

The DPRK allowed the International Atomic Energy Agency to monitor the moratorium on uranium enrichment while productive dialogues continue, as the US promised to offer 240,000 metric tons of nutritional assistance, KCNA said.

The IAEA treats the agreement as "an important step forward", said the agency's director general Yukiya Amano.

"Pending further details, we stand ready to return to Yongbyon to undertake monitoring activities upon request and with the agreement of the Agency's Board of Governors."

KCNA added that the US made it clear that sanctions against the DPRK are not targeting the civilian sector. Once the Six-Party Talks resume, the priority will be a discussion about lifting sanctions on the DPRK and providing light water reactors to the DPRK.

The agreements were the result of high-level nuclear talks between Pyongyang and Washington held last week in Beijing.

Both the US and the DPRK would like to finalize the agreement, said Huang, adding that the US government needs a political achievement before the presidential election in November, while the DPRK needs to solve its food shortage problem.

The US has achieved its goal of making the DPRK suspend its nuclear and missile program. The DPRK compromised because the US can only offer nutritional aid, which can only be sent out to women and children, not all people who lack food, Wang said.

"Pyongyang's compromise indicates its intensive attempt to improve ties with Washington," he added.

Wang said the agreement is not a breakthrough for the nuclear issues on Korean Peninsula and difficulties still remained ahead.

"If Pyongyang still feels being threatened by joint-military drills held by the US, Republic of Korea and Japan, it is likely to resume its nuclear plans," Wang said.

Meanwhile, White House spokesman Jay Carney said at a news conference on Wednesday in Washington that Pyongyang's agreement showed concrete measures that Washington considered "a positive first step toward complete and verifiable denuclearization of the Korean Peninsula in a peaceful manner".

Pyongyang's agreement obviously needed to be followed up by actions, said Carney, adding that Washington expected "a continuity in the behavior of the DPRK".

US Secretary of State Hillary Clinton said the agreement is "a modest first step in the right direction," adding that Washington continues to have profound concerns over a range of the activities by the DPRK.

The ROK hailed the outcome of the recent US-DPRK consultation in Beijing, the ROK foreign ministry said on Thursday.

Seoul hopes for the faithful implementation of the agreement, the ministry said.