Iranian Foreign Ministry spokesman Abbas Musavi says Tehran will continue to export fuel to Venezuela if the South American country requests more supplies.
Both Iran and Venezuela are under U.S. sanctions and Washington has sought to deter such shipments.
"Iran practices its free trade rights with Venezuela and we are ready to send more ships if Caracas demands more supplies from Iran," Musavi told a weekly news conference on June 1 that was broadcast live on state television.
Iran has sent five tankers of fuel to Venezuela, once South America's top oil producer, which is suffering from a gasoline shortage amid a ravaging economic crisis.
The United States has warned governments, seaports, shippers, and insurers that they could face measures if they aid the tankers.
So far four tankers have entered Venezuelan waters, with the Refinitiv Eikon analytical company saying on May 31 that the first two tankers that delivered fuel to Venezuela have started the return journey.
Tensions have been on the rise between longtime foes Tehran and Washington since 2018, when U.S. President Donald Trump withdrew the United States from a landmark 2015 nuclear deal between Iran and world powers and reimposed crippling sanctions that have battered the Iranian economy.