China inked new rules on the supervision of military equipment purchase contracts on Saturday, the official Xinhua news agency said.

The announcement came one day after President Xi Jinping had a video call with his U.S. counterpart Joe Biden during which they discussed the Ukraine war.

During the call, Biden warned China against supporting Russia’s attack on Ukraine. Biden also said China, which has called for a ceasefire in Ukraine, makes its own decisions.

The rules aim to improve efficiency in the supervision of military equipment purchase contracts and make sure good quality equipment is delivered to the army, Xinhua said, without giving specific details.

The rules will come into effect on Mar. 20.