The United States is increasing pressure on Venezuela as it issued new sanctions Thursday on the country’s oil industry and on members of President Nicolás Maduro’s family. In addition, the Trump administration took steps to keep the tens of millions of dollars worth of oil in the large oil tanker that the U.S. seized Wednesday off the country’s coast. 

As the country has been hurt by U.S. sanctions, Maduro’s government has been selling their oil through a web of tankers and middlemen, according to The New York Times. The new sanctions go after six shipping companies and three nephews of Maduro’s wife. 

The oil on the seized tanker came from a state-owned Venezuelan company but so far, U.S. authorities have only obtained a warrant to seize the tanker, but not the oil itself. 

“There is a legal process for the seizure of that oil, and that legal process will be followed,” White House press secretary Karoline Leavitt told reporters on Thursday.