A chemical leak in north-eastern China, which killed three people and left eight poisoned, poses no threat to the environment in either China or Russia, according to Russia’s Foreign Ministry.

Phosgene gas reportedly leaked from a canister at a plant in Heilongjiang province. The substance which is now widely used in industry was used in the First World War as a chemical weapon. Phosgene is a colourless, volatile liquid that is highly poisonous.

The leak occurred 400 kilometres from the border with Russia after canister was thrown away and was thought to have exploded.

It’s not the first incidence of a chemical spill in the region.

In November 2005, a large toxic spill poisoned the Songhua River carrying contaminated water into Russian territory. It caused considerable environmental damage along Russia's Amur River.

The incident strained relations between the countries as it took several days for China to inform Russia about the spill.