Iran has rejected U.S. accusations that it was behind an attack that disabled about half of Saudi Arabia's oil production, the biggest disruption to world crude supplies ever.
"These allegations are condemned as unacceptable and entirely baseless," Foreign Ministry spokesman Abbas Musavi said on September 16 in remarks broadcast by state TV.
U.S. officials have said that evidence from the September 14 attack showed that Iran was behind it, and not the Yemeni Huthi group that had claimed responsibility.
U.S. President Donald Trump warned on September 15 that the United States is "locked and loaded" and ready to retaliate in response to the attack on the world's largest oil-processing facility.
Saudi Arabia oil supply was attacked, Trump said on September 15 on Twitter. There is reason to believe that we know the culprit, are locked and loaded depending on verification, but are waiting to hear from the [Saudi] kingdom as to who they believe was the cause of this attack, and under what terms we would proceed!
While Washington was quick to point a finger, other countries urged restraint until the picture surrounding the attack, carried out by drones, was clearer.
British Foreign Secretary Dominic Raab called the attack "a wanton violation of international law," but he also said that "in terms of who is responsible, the picture is not entirely clear."
Similarly, China said it was not responsible to accuse others "in the absence of a conclusive investigation or verdict."
The weekend attack has rattled world energy markets.
Trump said he authorized the release of U.S. strategic petroleum reserves if needed to stabilize energy markets. The reserve contains about 630 million barrels of oil, according to official data, and past presidents have released quantities during times of crisis, if there are fears of skyrocketing prices.
At the start of trading on September 16, Brent crude soared by 19 percent to $71.95 a barrel, while the West Texas Intermediate rose by 15 percent to $63.34, according to BBC Business.
The September 14 attacks reduced production by 5.7 million barrels a day, state oil giant Saudi Aramco said -- nearly half the kingdom's output. That affects 5 percent of the world's daily oil production, Reuters and The Wall Street Journal reported.
Saudi officials said a third of crude output will be back online on September 16.
In pointing the finger at Tehran, U.S. officials noted the attacks came from a direction indicating that Iran was behind them and that cruise missiles may have been used, not drones as Iranian-backed Huthi rebels in Yemen had claimed.
Iran rejected U.S. accusations that it was behind the attack and warned that U.S. land and naval forces in the region were within range of its missiles.
The September 15 comments by top Iranian officials followed accusations from U.S. Secretary of State Mike Pompeo, who charged that Tehran had launched "an unprecedented attack" on global energy supplies.
"Tehran is behind nearly 100 attacks on Saudi Arabia while [Iranian President Hassan] Rohani and [Foreign Minister Mohammad Javad] Zarif pretend to engage in diplomacy," Pompeo said in the Twitter post.
Despite the rising tensions, the White House left open the door that Trump could meet with Rohani at the United Nations General Assembly in New York, which begins on September 17.
Musavi, who said earlier that the U.S. accusations were intended to justify "future actions" against Iran, all but ruled out such a meeting, saying "we have neither planned for this meeting, nor do I think such a thing would happen in New York."
A senior Iranian Islamic Revolutionary Guards Corps commander, meanwhile, warned that the country was ready for war.
"Everybody should know that all American bases and their aircraft carriers in a distance of up to 2,000 kilometers around Iran are within the range of our missiles," the semiofficial Tasnim news agency quoted commander Amirali Hajizadeh as saying.
Since March 2015, a Saudi-led coalition has been battling the Huthi rebels, which are part of a regional network of militant groups aligned with Iran. The Shi'ite insurgent group holds Yemen's capital, Sanaa, and other territory in the Arab world's poorest country.
The conflict has been in military stalemate for years.
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