Iran has warned the US to stop playing a blame game through "suspicious" attacks on oil tankers in the Middle East, describing the American behavior as "worrying".

The stern warning by Iran's Foreign Ministry spokesman Abbas Mousavi on Friday came after US Secretary of State Mike Pompeo offhandedly blamed Tehran for attacks on two oil tankers in the Gulf of Oman.

"The suspicious nature of incidents for oil tankers is not a joke. It is not only not funny, but it is also worrying and alarming," Mousavi said in a statement.

The attacks on Thursday morning sent shock waves through the world which was awaiting the news of a meeting between Japanese Prime Minister Shinzo Abe and Leader of the Islamic Revolution Ayatollah Seyyed Ali Khamenei in Tehran.

Pompeo said immediately, “It is the assessment of the United States government that the Islamic Republic of Iran is responsible for the attacks that occurred in the Gulf of Oman today.”

"It seems that for Mr Pompeo and other American statesmen, accusing Iran in the suspicious and unfortunate incident for tankers is the most convenient and simplistic job," Mousavi said.

"While Japan's prime minister is meeting with the number one figure of the Islamic Republic of Iran to reduce tensions, which clandestine hands seek to undermine these efforts in the region and who benefit from it?" he added.

The spokesman reminded that Iran was the first country to come to help the ships in distress and save their crew as quick as possible.

"The responsibility for ensuring the security of the Strait of Hormuz lies with the Islamic Republic of Iran, and we have shown that we have been able to help the sailors of the crashed ships and rescue them as quickly as possible."

Earlier on Friday, Iran's Foreign Minister Mohammad Javad Zarif rebuffed Pompeo's allegations, saying they were part of the “sabotage diplomacy” pushed by the "B-Team".

That the US immediately jumped to make allegations against Iran—w/o a shred of factual or circumstantial evidence—only makes it abundantly clear that the #B_Team is moving to a #PlanB: Sabotage diplomacy—including by @AbeShinzo—and cover up its #EconomicTerrorism against Iran. — Javad Zarif (@JZarif) June 14, 2019

The B-Team is a reference to hawkish US national security adviser John Bolton, Israeli Prime Minister Benjamin Netanyahu, Saudi Crown Prince Mohammed bin Salman and Abu Dhabi Crown Prince Mohammed bin Zayed Al Nahyan.

In a follow-up Twitter post, Zarif said, “I warned of exactly this scenario a few months ago, not because I'm clairvoyant, but because I recognize where the #B_Team is coming from.”

The UN Security Council met behind closed doors on Thursday and discussed the attacks at the request of the United States.

Washington's assessment, however, was not shared by other council members, who noted that there was no clear evidence linking Tehran to the attacks, diplomats said.

The Iranian mission to the UN, meanwhile, rejected the "unfounded" US accusations.

“Neither fabrications and disinformation campaigns nor shamelessly blaming others can change the realities. The US and its regional allies must stop warmongering and put an end to mischievous plots as well as false flag operations in the region.”