ABOARD AIR forCE ONE (Reuters). U.S. national defense adviser Jake Sullivan presented some guidelines on Wednesday regarding the kinds of Chinese support of Russia. This comes after the United States warned Beijing last week about possible dire consequences.

Sullivan spoke aboard Air Force One, en route from Washington to Brussels to join President Joe Biden at the NATO Summit. He stated that U.S. sanctions enforcement would examine whether China allows settlements of Russian payments and other countermeasures to export control laws since Russia invaded Ukraine.

He was asked for more detail and listed several instances when the United States could feel forced to act.

The U.S. will be looking for businesses that “try to backfill as a response to our export controls,” Sullivan explained. The act of providing a product to Russia after it has been affected by export restrictions is called backfilling.

If Chinese companies or others “choose to backfill” the U.S. has tools to ensure that can’t happen, he added.

Sullivan stated that the U.S., its G7 partners, and other countries are interested in and willing to respond to any “systematic effort, industrial-scale attempts to reorient settlements of financial payments etc.”