China will implement an upgraded version of emission standards for vehicles nationwide beginning July 1, the country’s environment ministry said on Tuesday, pressuring automakers to clear inventories of old models ahead of the new rules.

China will ban the production, import and sale of vehicles that do not comply with the National VI B emission standards, which include stricter requirements on pollutants including carbon monoxide of gasoline and petroleum vehicles, according to the statement from the Ministry of Ecology and Environment.

It will also require real-driving emission tests of the vehicles while driven on the road, which are not required under current standards of National VI A implemented since July 2020.

The ministry has granted a six-month grace period for sales of light vehicles that have yet to meet the requirements of RDE tests in the National VI B standards.

The plans for stricter auto emissions standards have added pressure to automakers and dealers to clear inventories of vehicles that do not meet the rule, leading to aggressive discounts on those models, Fitch Ratings analysts said in March.

According to the China Automobile Dealers Association, which called for a grace period under the new rules on auto sales, there was about 2 million vehicles in inventory that fail to meet the RDE tests under the upcoming new standards as of the end of March.