The US announced sanctions on Friday on four shipping companies and nine vessels involved in shipping oil from Venezuela.
The companies were named as Liberia-based Jennifer Navigation, Lima Shipping Corp and Large Range, which each own one tanker, and Italy-based PB Tankers, which owns six vessels.
The move follows last week's sanctions by the US Treasury on 34 vessels owned or operated by Venezuela's PDVSA state-run oil company and two companies and a vessel delivering oil to Cuba.
Lifeline to 'illegitimate regime'
The oil sector continued "to provide a lifeline to the illegitimate regime" of Venezuelan President Nicolas Maduro, the US Treasury stated.
The sanctions prevent US citizens having dealings with any of the companies and block their financial interests in the US.
Treasury Secretary Steven Mnuchin said in a statement on Friday: "We continue to target companies that transport Venezuelan oil to Cuba, as they are profiting while the Maduro regime pillages natural resources."
"Venezuela's oil belongs to the Venezuelan people, and should not be used as a bargaining tool to prop up dictators and prolong oppression," Mnuchin said.
Ex-spymaster found in Spain
Also on Friday, Spanish police arrested former Venezuelan spy chief Hugo Carvajal in Madrid. He was accused of having "coordinated the transportation of approximately 5,600 kilograms of cocaine from Venezuela to Mexico" in 2006. He denies the charge.
The retired general and former head of Venezuela's military intelligence is to appear before a Spanish court in Madrid on Saturday.
Carvajal had advised late Venezuelan leader Hugo Chavez and headed the security apparatus for more than 10 years. In 2014, he was Venezuela's consul on the Dutch Caribbean island of Aruba, which refused to extradite him to the US.
Three years later, Carvajal was back in Venezuela and serving as a lawmaker in the ruling party when he broke with President Nicolas Maduro's government over the president's plans to form a constitutional assembly, undermining the authority of the elected, opposition-controlled congress.
Support for Guaido
In mid-February, Carvajal announced his support for congressional leader and self-declared president Juan Guaido.
"We can't allow an army, in the hands of a few generals subjugated to Cuban instructions, to become the biggest collaborator of a dictatorial government that has plagued people with misery," he said at the time.
While Carvajal urged fellow members of the military to join him, few did so. But even this week he tweeted that he was confident Maduro would "leave by a decision of the Armed National Force."
jm/ng (Reuters, EFE)