BRUSSELS — The European Union on Thursday called for "maximum restraint" to avoid escalation after two Tankers were reportedly attacked in the Gulf of Oman, forcing their crews to evacuate the vessels.

The incident, the second involving shipping in the strategic sea lane in only a few weeks, came amid spiraling tensions between Tehran and Washington, which pointed the finger at Iran over tanker attacks in May.

Maja Kocijancic, spokeswoman for EU diplomatic chief Federica Mogherini, said the bloc was still gathering information on the incident, which involved one Norwegian and one Japanese-owned vessel.

"The region does not need further elements of destabilization and tensions and therefore her (Mogherini's) call and our call continues to be for maximum restraint and to avoid any provocations," Kocijancic said.

The US Fifth Fleet said its warships had received distress calls from two vessels in a "reported attack", while Iran said its navy had rescued 44 crew members after the ships caught fire in "accidents" off its coast.

In London, Britain said on Thursday it was deeply concerned by reports of explosions and fires on vessels in the Gulf of Oman.

"We are deeply concerned by reports of explosions and fires on vessels in the Gulf of Oman. We are in contact with local authorities and partners in the region," a British government spokeswoman said.

France's Foreign Ministry called for restraint and a de-escalation of tensions in the Gulf on Thursday.

"We call for restraint and de-escalation from all actors, with whom we are permanently in contact," Foreign Ministry spokeswoman Agnes von der Muhll told reporters in a daily online briefing. "We also recall our attachment to freedom of navigation, which must absolutely be preserved."

France operates a naval base in the United Arab Emirates.

In another development, state-run Kuwait Oil Tanker Company (KOTC) said on Thursday its vessels were operating as normal after suspected tanker attacks. The company is ready for any emergency and has taken all necessary precautionary measures to ensure the safe operation of its fleet, KOTC added. — Agencies