U.S. President Donald Trump on Friday signed an executive order that aims to block the seizure of Venezuelan oil revenue held in U.S. Treasury accounts.

The executive order states that the revenue, which is held in foreign government deposit funds, are “held solely for sovereign purposes” and that any court attempt to seize the funds will “materially harm the national security and foreign policy” of the U.S.

The order, which declared a national emergency, said the funds are the sovereign property of Venezuela held in U.S. custody for governmental and diplomatic means, and are not assets subject to private claims. Any use of judicial process against the funds will interfere with efforts to “ensure economic and political stability in Venezuela,” the order says.

Trump signed the order nearly one week after U.S. military forces captured Venezuelan leader Nicolás Maduro and his wife, Cilia Flores, in Caracas. Both were indicted on drug-trafficking charges and have pleaded not guilty.

Since the military operation, Trump has said that both nations “are working well together” on rebuilding Venezuela’s oil and gas infrastructure and that American oil giants will invest at least $100 billion in the South American country.