President Donald Trump objects to an effort by Congress to prevent his administration from recognizing Crimea as part of Russia.

Crimea is a region in Ukraine that has been occupied by Russia for several years, with the Russian Federation having claimed to have annexed the region in March 2014. Russian President Vladimir Putin has claimed the territorial matter is settled, but many in Washington disagree.

Language in the fiscal 2019 defense authorization, which Trump signed into law Monday during a ceremony at Fort Drum in upstate New York, purported to impose a funding blockade on the Pentagon acting on recognition of Crimea as part of Russia.

The literal text of the new law states: “None of the funds authorized to be appropriated by this Act or otherwise made available for fiscal year 2019 for the Department of Defense may be obligated or expended to implement any activity that recognizes the sovereignty of the Russian Federation over Crimea.”

The defense authorization law does allow for the provision to be waived, provided that the secretaries of Defense and State provide explanations to the relevant House and Senate committees.