National Security Advisor John Bolton answers questions from reporters as he announces that the U.S. will withdraw from a treaty with Iran during a news conference in the White House briefing room in Washington, October 3, 2018.

Attacks on four tankers off the United Arab Emirates coast of Fujeirah earlier this month are most likely the work of Iran, U.S. National Security Advisor John Bolton said Wednesday.

"I think it is clear these (tanker attacks) were naval mines almost certainly from Iran," Bolton told reporters in Abu Dhabi, though he declined to add details or evidence for the claim.

Iranian officials were not immediately available for a comment, but have previously denied involvement and called for an independent probe. An investigation including U.S. authorities is currently ongoing.

Bolton is meeting with Gulf allies to chart a course of action in response to what the Trump administration has cited as increased and serious threats from Tehran. While the White House has repeatedly said it is not seeking war or regime change, experts fear a miscalculation could lead to more serious confrontation.

The national security advisor added that Washington is trying to be "prudent" in its response to Iran and its proxies in the region.

Tensions have spiked this month following the tanker attack, which UAE authorities described as sabotage, and a subsequent drone attack on Saudi oil pumping stations claimed by Yemeni Houthi rebels, who are supported by Iran.

Tehran, under pressure from heavy U.S. sanctions, has announced an end to some of its commitments to the 2015 Iranian nuclear deal, which was meant to curtail the country's nuclear program in exchange for financial relief.