Vladimir Putin signed the new mutual defense pact between North Korea and Russia into law on Saturday, a move that may seek to provide a legal basis for DPRK troops’ participation in the Ukraine war.

The signing comes after the upper house of the Russian parliament ratified the Treaty on Comprehensive Strategic Partnership last week, following in the footsteps of the lower house.

Putin and his North Korean counterpart Kim Jong Un signed the treaty during their summit in Pyongyang in June, under which the both countries agreed to “immediately provide military and other assistance” if the other is attacked.