President Vladimir Putin promised help to North Korea build satellites and showed Kim Jong Un around Russia's most modern space launch facility on Wednesday before talks that were expected to include military matters.
Kim arrived at the Vostochny Cosmodrome, nestled among the forests of eastern Russia not far from the Chinese border, by train after crossing into Russia early on Tuesday.
When reporters asked whether Russia would help Kim build satellites, Putin replied: "That's why we came here. The leader of the DPRK shows great interest in rocket engineering; they are also trying to develop space."
Responding to a question about whether he and Kim would discuss military matters, Putin said they would discuss all issues. Russian Defence Minister Sergei Shoigu is attending the talks.
"I am glad to see you," Putin said as he shook Kim's hand for about 40 seconds at Vostochny. "This is our new cosmodrome."
Putin also congratulated Kim North Korean anniversaries, including 75 years since the establishment of North Korea in 1948.
Via a translator, Kim thanked Putin for the invitation and for the warmth of his reception. He then signed the visitor book in Korean: "The glory to Russia, which gave birth to the first space conquerors, will be immortal."
Russian state television said Kim asked Putin a large number of detailed questions during his tour of the space facility.
Russian media said Putin showed Kim around the building where Russia's new space booster, the Angara, is assembled. The 42.7-metre rocket launches payloads into low Earth orbit.
The United States has accused North Korea of providing arms to Russia, but it is unclear whether any deliveries have been made. Both Russia and North Korea have denied those claims, but promised to deepen defence cooperation.
"As neighbours, our countries implement cooperation in sensitive areas that should not become the subject of public disclosure and announcement," Kremlin spokesman Dmitry Peskov said. "But this is quite natural for neighbouring states."