The Treasury Department slapped sanctions on Nicolas Maduro on Monday, alleging that Venezuela’s president has attempted to undermine democracy and the rule of law in his country.

On Sunday, Venezuela held a controversial election to create the National Constituent Assembly (ANC), a constitutional assembly that would grant Maduro’s party with sweeping power. But many countries said they would not recognize that vote.

Treasury Secretary Steven Mnuchin said that those who participate in the illegitimate assembly could face “future U.S. sanctions for their role in undermining democratic processes and institutions in Venezuela.”

The ANC, which many expect to be stacked with Maduro supporters, would be able to rewrite the country’s constitution.