Russia has taken a step closer to ratifying a defence pact with North Korea that provides “mutual assistance” if either country faces aggression.

MPs in Russia’s lower house of parliament voted unanimously to ratify the treaty, meaning it will now be sent to the upper house for approval.

Both houses serve as rubber stamps for the Kremlin, meaning it is certain to be approved.

It comes after Washington confirmed that it had seen evidence that North Korea had sent at least 3,000 troops to Russia for training and possible deployment to Ukraine.

South Korea believes as many as 12,000 troops, including special forces, could be sent to fight on the front line by the end of the year. Seoul is considering sending lethal weapons to Ukraine in response.

The West believes North Korea has already provided Moscow with weapons to use in its invasion of Ukraine, reflecting deepening military relations between the two countries.