The Iranian tanker Forest arrived Tuesday at a Venezuelan port carrying 275,000 barrels of gasoline, and the Fortune arrived a day later, said Russ Dallen, head of the Miami-based investment firm Caracas Capital Markets, who tracks Venezuela shipments.

A third tanker, the Faxon, is expected to reach the South American nation this weekend, Dallen said.

Dallen and others say there is little more that the U.S. do, short of the U.S. Navy intercepting the tankers at sea and risking an accident with a highly flammable cargo. If the U.S. Navy were to get involved that also risks retaliation by Iran in the Persian Gulf, and a possible military conflict.

“The U.S. could win a war with Iran, but do we really want to get there through a series of escalating moves?” said Dallen.

“Ultimately, Venezuela cannot continue buying all the gasoline needed as it doesn’t have enough money. So, Venezuela gets gas temporarily and Iran gets a little money or gold — it is not yet a sustainable business,” said Dallen.