MOSCOW / North Korea's leader vowed closer ties with Moscow on Wednesday, saying his isolated country would "always be with Russia" as President Vladimir Putin hosted Kim Jong Un at a Far East spaceport.

Russia has become a pariah in the West after launching full-scale hostilities in Ukraine last year and has looked to strengthen alliances with other hardline leaders ostracised by Western countries.

Putin said Moscow could help North Korea build satellites and hinted the two countries might also discuss military cooperation, saying he was "very glad" to see Kim in Russia.

Kim told Putin that North Korea would make bilateral ties with Russia its "number one priority" and that Russia was facing down "hegemonist forces" seeking to undermine its security.

"We have always expressed full and unconditional support for all the measures taken by the Russian government, and I take this opportunity again to affirm that we will always be with Russia," Kim said, according to footage broadcast on Russian TV.

Their one-on-one talks as well as discussions with delegations lasted around two hours before the leaders proceeded to an official dinner in Kim's honour, Russian state-run news agencies said.

US officials and experts have said Russia is interested in buying North Korean ammunition to use in the conflict in Ukraine -- an arms deal that would defy global sanctions.

The two leaders met at the Vostochny Cosmodrome in Russia's Far East, with footage released by the Kremlin showing the pair shaking hands enthusiastically as Kim arrived.

The two then toured assembly and launch facilities for the Angara and Soyuz-2 space rocket launchers before sitting down for talks with their delegations.

While Kim was in Russia, Pyongyang fired two ballistic missiles on Wednesday, the South Korean military said, the latest in a string of sanctions-busting tests.

Experts say Russia will likely use the talks to seek artillery shells and antitank missiles from North Korea, which wants advanced satellite and nuclear-powered submarine technology in return.

"We'll talk about all the issues, without haste. There is time," Putin said, when asked by reporters whether military cooperation would be on the agenda.

Kim, who travelled overland to Russia in his bullet-proof train, was accompanied by an entourage that suggested the summit would have a strong military focus.

Among the top military officials accompanying Kim were Korean People's Army Marshal Pak Jong Chon and Munitions Industry Department Director Jo Chun Ryong, according to the North's state media. 

Russian Defence Minister Sergei Shoigu took part in the talks with Kim, as did Foreign Minister Sergei Lavrov, images on Russian state television showed.

Ahead of the announcement of the talks, Russian news agencies published images of Kim and Putin touring the vast space centre.

"The leader of the DPRK shows great interest in rocket technology, and they are trying to develop (their presence in) space," Putin said, referring to North Korea by its official name.

Kim thanked Putin for inviting him to visit, despite the Russian leader's "busy schedule".

Kim had earlier stressed the trip -- his first post-pandemic foreign travel -- showed North Korea was "prioritising the strategic importance" of its Russia ties. 

- Tactical gains -

The meeting at the cosmodrome is symbolic, especially as Pyongyang failed twice recently in its bid to put a military spy satellite into orbit, experts said.

Russia is eager for North Korea's stockpile of artillery shells, while Pyongyang is looking for help with satellite technology and upgrading its Soviet-era military equipment, An Chan-il, a defector-turned-researcher who runs the World Institute for North Korea Studies, told AFP.

"If North Korea's multiple rocket launchers and other artillery shells are provided to Russia in large quantities, it could have a significant impact on the war in Ukraine," he said.

Russia's natural resources minister Alexander Kozlov greeted Kim when he arrived in the country, giving him historic autographed photographs of Soviet cosmonauts, including Yuri Gagarin, Kozlov's ministry told TASS.

The White House warned last week that North Korea would "pay a price" if it supplies Russia with weaponry for the conflict in Ukraine.

Kim is also risking the displeasure of his other major ally Beijing by meeting Putin, Vladimir Tikhonov, professor of Korean studies at the University of Oslo, told AFP.

"China will be hardly too happy about Russia entering into what Chinese consider their monopoly territory," he said, adding Beijing would be worried about the regional destabilisation impact of any transfer of Russian military technology to Pyongyang.

Kim and Putin "may conduct an exchange of North Korea's old-age, Soviet-type ammo for Russia's newer military tech or hard currency (or wheat)."

"Tactically, they both gain, by getting what they need right now. In a longer term though, Russia's important ties to Seoul will be dealt irreparable damage."