Iran on Sunday discussed its plans for nuclear-powered ships with Yukiyo Amano, head of the UN’s International Atomic Energy Agency (IAEA), AFP reported.
Details for the plans are to be presented within three months, according to the report.
Amano did not comment on Tehran's plans to produce nuclear-powered engines, but said Iran had so far met all of its commitments under last year's nuclear deal with world powers.
Iranian President Hassan Rouhani told Amano he hoped "Iran and the IAEA can have good technical cooperations on the production of nuclear propellants for maritime transport," said the government's website.
In an earlier meeting with Amano, Ali Akbar Salehi, head of Iran's Atomic Energy Organization said the two "discussed the nuclear-powered engines in detail."
He added that talking points included the level of uranium-enrichment required for the ships.
"This is not a simple matter that can be decided quickly. We have three months to review it," he told reporters, according to AFP.
"Normally, the enrichment for such engines is between five percent and 90 percent. It depends on the type of engine and the time and goal we want to reach," said Salehi.
Rouhani last week ordered Iranian scientists to start developing systems for nuclear-powered marine vessels, in response for what he termed was the United States’ “violation” of the nuclear deal between his country and world powers.
His directive came after both houses of Congress voted overwhelmingly in favor of extending the Iran Sanctions Act (ISA).
Tehran says Washington has breached the nuclear accord by renewing the Iran Sanctions Act, even though almost all of its measures remain suspended under the deal.
"We adhere to our commitments and we will not trigger the violation of commitments," Rouhani said after meeting with Amano, repeating that the renewal of sanctions "contradicts" the accord.
"As long as the other sides remain committed to their commitments in the (nuclear deal), the Islamic Republic of Iran will continue to act on its commitments," he added, according to AFP.
White House spokesman Josh Earnest last week downplayed Rouhani’s directive, arguing that the move is not a violation of Iran's commitments under the nuclear deal.
"The announcement from the Iranians today does not run counter to the international agreement to prevent Iran from obtaining a nuclear weapon," Earnest told a news briefing.
Rouhani’s directive came several days after Iranian lawmakers threatened to pass legislation to resume the country’s nuclear activities response to Congress extending the sanctions.