Russian President Vladimir Putin, Kim Jong Un meet in North Korea

LONDON -- Russia's President Vladimir Putin has arrived in Pyongyang, North Korea, early Wednesday, amid isolation from the international community resulting from Russia's prolonged invasion into Ukraine.

North Korean leader Kim Jong Un met Putin at the plane ramp and walked along a red carpet lined with soldiers of the honor guards prepared by the North Korean regime. They began speaking to each other immediately after Putin's landing at the Pyongyang International Airport, ABC News reported.

The two leaders will discuss further cooperation on a two-day trip in the wake of their meeting last September in Russia.

Russia and North Korea will sign a Comprehensive Strategic Partnership Agreement at the highest level during the trip, according to Russia's presidential order.

The Kremlin revealed Putin's letter published in North Korea's state newspaper Tuesday in which Putin referred to the relationship with North Korea as "friendship" and "neighborliness."

"Today, as before, Russia and the Democratic People's Republic of Korea are actively advancing their multifaceted partnership," Putin said in an article published in North Korea's state newspaper Tuesday morning. "We highly appreciate the DPRK's unwavering support for Russia's special military operation in Ukraine."

In the letter, Putin also hinted at closer cooperation, unrestrained by the Western world. He wrote of a plan to "develop alternative trade and mutual settlements mechanisms not controlled by the West," calling for a joint movement to oppose the unilateral restrictions that Russia believes to be illegitimate.

Analysts in Seoul are also anticipating what may come out of the talks between the two notorious leaders who likely know that there is high interest from the international community in this summit.

SEE ALSO: Putin offers truce if Ukraine exits Russian-claimed areas and drops NATO bid. Kyiv calls it 'absurd'

"Putin's visit is in part to thank North Korea for acting as an 'arsenal for autocracy' in support of his illegal invasion of Ukraine," Leif-Eric Easley, professor of international studies at Ewha Womans University in Seoul, told ABC News. "Moscow's transfer of sensitive military technologies to Pyongyang would not only violate UN sanctions but could also destabilize the Korean Peninsula and East Asia."

"It seems Putin is paying the visit to keep his words, and also to show the world that Russia-North Korea solidarity is ironclad," Sang-Jung Byun, Director of North Korean Studies at the Seoul-based Institute for National Security Strategy, told ABC News. "There is potential that Russia may bring up connecting railways again, which will become a huge source of foreign currency if possible."

Another agenda item likely to be on the table is cooperation in space technology. North Korea is in desperate need of Russia's help to upgrade its ambitious space program at the moment. The regime failed to launch its second reconnaissance satellite, and the satellite that is up and running in space is also questioned for its performance.

"A noticeable difference from Putin's North Korea visit back in 2000 is that the heads of space corporation, railways and also energy are included in the entourage," Seoul's Unification Ministry official told journalists Tuesday. "We feel a need to keep a close eye on possible cooperation in space technology since the latest Russia-North Korea summit was held at the Vostochny Cosmodrome last year."

The two leaders met nine months ago during Kim's visit to the Vostochny Cosmodrome in far east Russia last September. For Putin, it is the first visit to Pyongyang in 24 years, when he as a new Russian leader met with the late North Korean leader Kim Jong Il.