According to a new report released within the United Nations, Kim Jong Un’s North Korean regime has been exporting materials and supplies that could be used in the production of chemical weapons to Syria, where Bashar al-Assad’s regime has been repeatedly accused of using them against civilians in rebel held territory.

The report, which was written by an international panel of experts hailing from different nations and scientific disciplines, goes on to accuse North Korea of providing direct support to Assad in known chemical weapons facilities inside Syria. The list of equipment provided by North Korea to assist in the production of chemical weapons includes acid-resistant tiles and other more common goods like valves and thermometers.

North Korea is rumored to possess the largest stockpile of chemical and biological weapons on the planet, according to an assessment released by South Korean intelligence agencies last year. The nation was further implicated in the assassination of Kim Jong Un’s older half-brother, Kim Jong Nam, who was killed using a chemical weapon known as VX in Malaysia last year.

These allegations come only days after Syria was once again accused of carrying out chlorine gas attacks against civilians and rebels living in Eastern Ghouta, a suburb in the Syrian capital, Damascus. Formally, Assad’s regime has denied the use of chemical weapons, as have their military backers, the Russians, though human rights groups operating in Syria have reported treating the victims of chemical attacks carried out by Syrian forces.

Last year, President Trump ordered a cruise missile bombardment of the Syrian airfield believed to have scrambled the aircraft responsible for a sarin gas attack against civilians in Idlib, though Assad claimed innocence in that incident as well.

The U.N. report goes on to claim that the relationship between Kim and Assad as been mutually beneficial, as it has permitted Syria to continue its use of banned chemical weapons while simultaneously providing an influx of funding to Kim Jong Un’s nuclear and ballistic weapons programs. North Korea has been the subject of a multitude of international sanctions aimed at curbing their rapidly advancing nuclear program, thus far, to no avail.

According to the analysis of Bruce Bechtol, a former Korea analyst at the United States Defense Intelligence Agency who is now a professor at Angelo State University in Texas, illegal weapons trading with Syria “has been a boon for the North Korean military-industrial complex.” In a book Bechtol will release later this year, he claims, he’ll outline the ways in which North Korea has supported Syrian chemical weapons manufacturing as far back as the 1990s.

The U.N. reportedly claims that chemical weapons components were included in at least 40 shipments between North Korea and Syria between 2012 and 2017 that had previously gone unreported. Those shipments also included ballistic missile components that could arguably be used in some non-military applications, but still violate international sanctions.