The Treasury also designated four entities owned or controlled by Cartes.

The institution accused Cartes of participating in corrupt activities before, during and after his term as president, alleging the basis of his career depended on "corrupt means for success."

Cartes is the head of Paraguay's ruling Colorado party and important backer of its candidate in this year's presidential election.

The Treasury said Cartes joined the Colorado Party in 2009, providing financial aid and incentives to push the group to eliminate a requirement allowing him to run as the party's presidential candidate.

He also paid party members up to $10,000 each to support his candidacy before 2013 elections, the Treasury said.

As president, Cartes made cash payments to officials in exchange for their backing, the Treasury alleged. He reportedly made monthly payments to legislators from $5,000 to $50,000 per member.

Reuters could not immediately reach Cartes or Velazquez for comment.

(Reporting by Brendan O'Boyle and Kylie Madry)