Venezuela has launched a complaint at the World Trade Organization to challenge U.S. sanctions, saying that a ban on travel by blacklisted individuals and trade restrictions break WTO rules, a WTO filing showed on Tuesday, Reuters reported.

In its second-ever WTO complaint, filed on Dec. 28, Venezuela also cited U.S. rules on sales of gold and discriminatory treatment of Venezuela’s debt and transactions in digital currency as breaches of the international rules.

There was no immediate reaction from the United States, which has been tightening sanctions against the government of President Nicolas Maduro in recent months, targeting senior officials and Maduro’s wife and allies, as well as banning sales of Venezuelan gold.