SEOUL, Sep 13 (Reuters) - North Korean leader Kim Jong Un has said his visit to Russia was a clear show of the "strategic importance" of the two countries' relations, state media KCNA reported on Wednesday (Sep 13).

Kim arrived in Russia by private train on Tuesday for talks with President Vladimir Putin amid warnings from Washington the two countries should not trade weapons.

"Kim Jong Un said that his visit to the Russian Federation ... is a clear manifestation of the stand of the WPK and the government of the DPRK prioritizing the strategic importance of DPRK-Russia relations," the KCNA report said.

The DPRK stands for North Korea's official name, the Democratic People's Republic of Korea, while the WPK is the Workers' Party of Korea, the sole ruling party in the reclusive country.

Images released by KCNA showed Kim arriving at the train station in the border town of Khasan on Tuesday morning and being greeted by senior officials from Moscow and elsewhere.

He is also shown meeting with Russia's Natural Resources Minister Alexander Kozlov.

His movements since are unclear but Japan's Kyodo news agency and South Korean media have reported that he might meet Putin at the Vostochny cosmodrome in eastern Russia.

The trip marks Kim's first visit to Russia in nearly four years and his first foreign visit after the worldwide public health crisis, according to KCNA, referring to the COVID-19 pandemic.

His visit seeks to put North Korea-Russia relations of friendship and cooperation on a "fresh higher level", the report said.