DUBAI, United Arab Emirates (AP) — U.S. diplomats warned Saturday that commercial airliners flying over the wider Persian Gulf faced a risk of being “misidentified” amid heightened tensions between the U.S. and Iran.

The warning relayed by U.S. diplomatic posts from the Federal Aviation Administration underlined the risks the current tensions pose to a region crucial to global air travel. It came as Lloyd’s of London warned of increasing risks to maritime shipping in the region.

Meanwhile, oil giant ExxonMobil began evacuating staff from Basra, Iraq, where the U.S. Consulate has been closed for months following a rocket attack America blamed on Shiite militias backed by Iran, local authorities said. The island nation of Bahrain also ordered its citizens out of Iraq and Iran over regional tensions.

Concerns about a possible conflict have flared since the White House ordered warships and bombers to the region to counter an alleged, unexplained threat from Iran that has seen America order nonessential diplomatic staff out of Iraq.

President Donald Trump since has sought to soften his tone. Iranian Foreign Minister Mohammad Javad Zarif also stressed Saturday that Iran is “not seeking war,” comments seemingly contradicted by the head of the Revolutionary Guard, who declared an ongoing “intelligence war” between the nations.

Regional tensions remain high. Authorities allege that a sabotage operation targeted four oil tankers off the coast of the United Arab Emirates, and Iran-aligned rebels in Yemen claimed responsibility for a drone attack on a crucial Saudi oil pipeline.

Saudi Arabia directly blamed Iran for the drone assault, and a local newspaper linked to the Al Saud royal family called on Thursday for America to launch “surgical strikes” on Tehran.

This all takes root in Trump’s decision last year to withdraw the U.S. from the 2015 nuclear accord between Iran and world powers and impose wide-reaching sanctions. Iran just announced it would begin backing away from terms of the deal, setting a 60-day deadline for Europe to come up with new terms or it would begin enriching uranium closer to weapons-grade levels. Tehran long has insisted it does not seek nuclear weapons, though the West fears its program could allow it to build atomic bombs.

The order relayed Saturday by U.S. diplomats in Kuwait and the UAE came from an FAA Notice to Airmen published late Thursday in the U.S. It said that all commercial aircraft flying over the waters of Persian Gulf and the Gulf of Oman needed to be aware of “heightened military activities and increased political tension.”

This presents “an increasing inadvertent risk to U.S. civil aviation operations due to the potential for miscalculation or misidentification,” the warning said. It also said aircraft could experience interference with its navigation instruments and communications jamming “with little to no warning.”

The Persian Gulf has become a major gateway for East-West travel in the aviation industry. Dubai International Airport in the United Arab Emirates, home to Emirates, is the world’s busiest for international travel, while long-haul carriers Etihad and Qatar Airways also operate in the region.