North Korea has been sending supplies to Syria that could be used to produce chemical weapons, a United Nations Security Council diplomat has told CNN.

Speaking on condition of anonymity, the diplomat said that North Korea had sent acid-resistant tiles, valves and thermometers to Syria. The diplomat was citing a report on North Korea authored by a UN panel of experts.

The same report also claims North Korean missile experts visited Syria in 2016 and 2017, after the chemical weapons supplies had been sent to the Middle Eastern state.

During one of the trips, the technicians stayed at Syrian military facilities. A UN member state reported to the panel of experts that scientists from North Korea may still be operating in Barzeh, Adra and Hama.

The details come just two days after the Syrian regime was accused of carrying out a chlorine gas attack on Eastern Ghouta, a suburb in the Syrian capital, Damascus.

Syrian President Bashar al-Assad's regime has repeatedly denied claims that it uses chemical weapons. Medical aid organizations, however, say they have routinely treated victims of chemical attacks and blame government forces, as the country's war nears its seventh anniversary. The US and other countries have made the same accusations against the Assad government.