Russian Foreign Minister Sergey Lavrov thanked North Korea for its support for Russia’s war on Ukraine as he arrived in Pyongyang, days after the United States said the North had transferred munitions to Russia to boost its warfighting capabilities.

Russian state television ran footage of crowds greeting Lavrov in the pouring rain in Pyongyang on Wednesday alongside a welcoming party waving pompoms. Lavrov said his visit was an opportunity to discuss implementing the unspecified agreements between Russian President Vladimir Putin and North Korean leader Kim Jong Un when they met at Russia’s Vostochny Cosmodrome in September.

Lavrov later attended a reception where North Korean Foreign Minister Choe Son Hui said the countries were building an “unbreakable comradely relationship” under the “strategic” decisions and leadership of Kim and Putin, the North’s official Korean Central News Agency said.

Lavrov in a speech said Russia deeply values North Korea’s “unwavering and principled support” for its war on Ukraine as well as Pyongyang’s decision to recognize the independence of Russian-backed separatist regions in eastern Ukraine, according to his comments published by Russia’s Foreign Ministry.

“We are fully aware that many countries worldwide share similar viewpoints and assessments, but only a select few, such as the DPRK, explicitly declare their solidarity with Russia and can express it openly,” Lavrov said, using the initials of North Korea’s formal name, the Democratic People’s Republic of Korea.

Lavrov also praised North Korea for “firmly defending its sovereignty and security, remaining unfazed by any pressure of the U.S. and the West,” and that Russia fully supports the policies of Kim’s government to protect its security and economic interests, KCNA said.

Earlier in the week, Lavrov accompanied Putin on a visit to Beijing that underscored Chinese support for Moscow’s war in Ukraine.

The September meeting between Kim and Putin triggered Western concerns about a potential arms alliance in which North Korea would supply Russia with munitions to fuel its war in Ukraine in exchange for advanced Russian technologies to boost Kim’s military nuclear program.

After arriving in Pyongyang, Lavrov hailed Putin’s meeting with Kim as historic, saying their talks demonstrated the countries’ “deep interest in the development of comprehensive cooperation.”

The White House has said North Korea has delivered more than 1,000 containers of military equipment and munitions to Russia.

White House National Security Council spokesman John Kirby said the U.S. believes Kim is seeking sophisticated Russian weapons technologies in return for the munitions to boost North Korea’s military and nuclear program.

The recently flurry of diplomacy between Moscow and Pyongyang underscores how their interests are aligning in the face of their separate, intensifying confrontations with the United States.

Russian Defense Minister Sergei Shoigu visited North Korea in July for meetings with Kim, who also invited him to a military parade in Pyongyang that showcased North Korean intercontinental ballistic missiles designed to target the United States. Kim’s visit to Russia in September was his first foreign trip since the start of the COVID-19 pandemic.

During his two-day visit, Lavrov is expected to meet with Choe. Putin has accepted an invitation from Kim to visit North Korea, but the timing has not been announced.