The United States has reportedly threatened Venezuela and Cuba against letting in two Iranian ships that are claimed to be headed to South American shores with a weapons cargo.

Citing an unnamed senior official with the administration of US President Joe Biden, Politico claimed the ships are believed to be carrying weapons from Iran to Venezuela under a deal between the two countries during the administration of former President Donald Trump.

“The delivery of such weapons would be a provocative act and understood as a threat to our partners in the Western Hemisphere,” the official said in a statement to Politico. “We would reserve the right to take appropriate measures in coordination with our partners to deter the transit or delivery of such weapons.”

The vessels are said to have already traveled a significant distance across the Atlantic Ocean, completing more than half the journey from Iran to Venezuela, marking the first time the Iranian navy has rounded Cape Town, South Africa, to get far into the Atlantic.

During his tenure, Trump withdrew US recognition of Nicolas Maduro as Venezuelan president and pulled Washington out of the 2015 Iran nuclear deal. Under Trump, Washington tightened its economic sanctions on both the Iranian and Venezuelan nations.

“The sale of the Iranian weapons happened one year ago under the previous [US] administration and like many situations related to Iran under the previous administration — including the breakout of Iran’s nuclear program following the Trump administration’s reckless withdrawal from the [Iran nuclear deal] — we are working to resolve it through diplomacy,” the US official said.

“But to be clear, Iran sold weapons to Venezuela over a year ago, which we believe was to test the Trump administration’s maximum pressure posture,” he said.

Meanwhile, hawkish US Senator Marco Rubio claimed in a tweet on Thursday that Venezuela had bought military equipment from Iran and then invited the Iranians into the Western Hemisphere.

“So don’t be surprised if in less than 3 weeks, we have Iran’s largest military vessel & their most modern warship (a guided missile corvette) patrolling the Gulf of Mexico,” Rubio claimed.