The United States and Russia are working closely on a shared goal of ending North Korea's nuclear and missile programs, the State Department said Wednesday amid reports North Korean leader Kim Jong-un plans to visit Moscow to attend World War II victory celebrations.

"We closely coordinate with our allies and partners, including Russia, to counter -- whether through persuasion or pressure -- the threat to global security posed by the DPRK's (North Korea's) nuclear and ballistic missile programs," the State Department spokesperson said.

"We have seen some indications of increased economic engagement between Russia and the DPRK, but our alignment on the core goal of denuclearization remains as strong as ever," the official said in comments to Yonhap News Agency.

The official, however, declined comment on reports that North Korean leader Kim Jong-un plans to visit Moscow in May to attend celebrations marking the 70th anniversary of the Soviet Union's victory in World War II.

"We have seen reports that Kim Jong-un will visit Moscow later this year. I would refer you to the government of Russia for information on this possible visit," the spokesperson said.

Earlier Wednesday, the Kremlin said in response to a question from Yonhap that some 20 foreign heads of state have confirmed that they will attend the celebrations in Moscow in May, and the North's leader is among them.

Should Kim's visit be realized, it would mark his first foreign trip since he took power after his father, Kim Jong-il, died in late 2011. The visit would also underscore the North's strengthening relations with Russia at a time when Pyongyang's ties with China remain sour.

The State Department official stressed Russia is a major stakeholder in the international nonproliferation regime.

"When senior Russian officials have met with their North Korean counterparts, they have consistently delivered a tough message on the need for the DPRK to abandon its nuclear and ballistic missile programs and abide by its international commitments and obligations," the official said. (Yonhap)