SEOUL, South Korea (AP) — North Korea and Russia reached a new agreement for expanding economic cooperation following high-level talks in Pyongyang this week, the North’s state media said Thursday, as they continue to align in the face of their confrontations with Washington.

North Korea’s official Korean Central News Agency didn’t elaborate on the details of the agreement signed Wednesday between its senior trade officials and a Russian delegation led by Alexandr Kozlov, the country’s minister of natural resources and ecology. The Russian news agency Tass on Tuesday said officials following an earlier round of talks agreed to increase the number of charter flights between the countries to promote tourism.

Kozlov, who arrived in North Korea on Sunday, met with North Korean leader Kim Jong Un and his top economic official, Premier Kim Tok Hun, before returning home on Wednesday, KCNA said. During Kozlov’s visit, Russian President Vladimir Putin’s gifted Pyongyang’s Central Zoo with more than 70 animals, including lions, bears and several species of birds, according to Tass, in another display of the countries’ growing ties.

Kim Jong Un in recent months has prioritized relations with Moscow as he attempts to break out of international isolation and strengthen his footing, actively supporting Putin’s war on Ukraine while portraying the North as a player in a united front against Washington.

Kim has yet to directly acknowledge that he has been providing military equipment and troops to Russia to support its fighting against Ukraine. South Korea’s National Intelligence Service told lawmakers in a closed-door briefing on Wednesday that an estimated 11,000 North Korean soldiers in late October were moved to Russia’s Kursk region, where Ukrainian troops seized parts of its territory this year, following their training in Russia’s northeast.

The spy agency believes the North Korean soldiers were assigned to Russia’s marine and airborne forces units and some of them have already begun fighting alongside the Russians on the frontlines, said Lee Seong Kweun, a lawmaker who attended the meeting. U.S., South Korean and Ukrainian officials have claimed that the North has also been supplying Russia with artillery systems, missiles and other equipment.

North Korea would be possibly getting anywhere between $320 million to $1.3 billion annually from Russia for sending its troops to Ukraine, considering the scale of the dispatch and the level of payments Russia has been providing to foreign mercenaries, according to a recent study by Lim Soo-ho, a South Korean analyst at an NIS-run think tank.