Venezuela's Maduro to visit Iran following oil shipments
"I am obliged to go to personally thank the people," Maduro said in a television address. He did not specify a date for the visit.
The news comes as Iran's foreign ministry said the country was willing to continue fuel shipments to Venezuela if it was required.
The oil deals have attracted the ire of the US, as it has imposed sanctions on both countries.
The US has closely monitored the shipments, concerned that Iran and Venezuela were taking their long-standing ties to a new strategic level.
The Iranian tankers have run the gauntlet of US warships arrayed off the Venezuelan coast, after Washington announced last month that it was stepping up its naval presence, arguing there was an increase in organised crime.
Venezuela has been in recession for six years, its economy in shambles, and its citizens struggling with shortages of basic necessities such as food and medicines.
US sanctions have targeted Venezuelan oil exports, starving Caracas of vital income. The US has also sanctioned El Aissami and accused him of drug trafficking.
Venezuela is almost entirely dependent on its oil revenues but its production has fallen to roughly a quarter of its 2008 level.
Venezuelan President Nicolas Maduro's government blames that on US sanctions, including against state oil company PDVSA, but many analysts say the regime has failed to invest in or maintain infrastructure.
Read more: Cash-strapped Venezuela empties vaults to send tons of gold to long-time ally Iran
Falling oil prices since 2014 have exacerbated Venezuela's economic crisis.
Venezuela has the world's largest proven oil reserves, but its capacity to refine crude into gasoline is limited.
Last month, the oil ministry revealed that the price of Venezuelan crude had fallen to its lowest level in more than two decades, at less than $10 a barrel. Last year it averaged $56.70.
Agencies contributed to this report.
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