Saudi Arabia will take appropriate steps to respond to an attack on its oil facilities if, as expected, a Saudi investigation confirms that Iran is responsible, a senior official said on Saturday, as Iran's top commander warned that any country that attacks the Islamic republic will become the "main battlefield".
The comments were the latest salvos in the diplomatic crisis between arch-foes Tehran and Washington after attacks on Saudi Arabia's oil infrastructure and US President Donald Trump's decision to send American troops to bolster the kingdom's defences.
Minister of State for Foreign Affairs Adel Al Jubeir said the probe would prove that the September 14 strikes came from the north and that Iran bore responsibility, a charge Tehran denies.
"The kingdom will take the appropriate measures based on the results of the investigation, to ensure its security and stability," Mr Al Jubeir told a news conference, declining to speculate about specific actions.
"We are certain that the launch did not come from Yemen, it came from the north. The investigations will prove that."
Yemen's Houthi rebels have claimed responsibility for the strikes on Saudi energy giant Aramco's Abqaiq processing plant and Khurais oilfield, which initially halved the kingdom's oil output, but the US says it has concluded the attacks involved cruise missiles from Iran and amounted to "an act of war".
"Be careful, a limited aggression will not remain limited. We will pursue any aggressor. We are after punishment and we will continue until the full destruction of any aggressor," the head of Iran's Islamic Revolutionary Guard Corp, Major General Hossein Salami, said in remarks broadcast on state TV.
"Whoever wants their land to become the main battlefield, go ahead," he told a news conference in Tehran.
"We will never allow any war to encroach upon Iran's territory.
"We hope that they don't make a strategic mistake", he said, listing past US military "adventures" against Iran.
Saudi Arabia, which has been involved in a five-year war across its southern border in Yemen, has said Iran "unquestionably sponsored" the attacks.
The kingdom says the weapons used in the attacks were Iranian-made, but it stopped short of directly blaming its regional rival.
Maj Gen Salami was speaking at Tehran's Islamic Revolution and Holy Defence museum during the unveiling of an exhibition of what Iran says are US and other drones captured in its territory.
It featured a badly damaged drone with US military markings said to be an RQ-4 Global Hawk that Iran downed in June, as well as an RQ-170 Sentinel captured in 2011 and still intact.
The United States on Friday imposed more sanctions, targeting the Central Bank of Iran, which was already under US sanctions, the National Development Fund of Iran - the country's sovereign wealth fund - and an Iranian company that US officials say is used to conceal financial transfers for Iranian military purchases.
Mr Trump said they were the toughest sanctions the US had ever imposed on another country.
"This is a sign of US desperation ... When they repeatedly sanction the same institution, this means their attempt at bringing the Iranian nation to its knees under 'maximum pressure' has failed," Foreign Minister Mohammad Javad Zarif told reporters in remarks shown on state television.
He was arriving in New York for the annual UN General Assembly next week, where he is expected to meet the foreign ministers of the remaining signatories to the 2015 nuclear deal.
In a further bout of fiery rhetoric against Saudi Arabia from a key Iranian ally, Lebanon's Hezbollah warned Saudi Arabia on Friday against betting on a war against Iran because it would destroy the country and urged Riyadh to halt the war in Yemen instead of buying more air defences.
"Don't bet on a war against Iran because they will destroy you," Hezbollah leader Sayyed Hassan Nasrallah said in a televised speech. "Your house is made of glass and your economy is made of glass," he said.
Iran denied reports that a successful cyber attack had struck its oil infrastructure.
"Contrary to Western media claims, investigations done today show no successful cyber attack was made on the country's oil installations and other crucial infrastructure," the government's cyber security office said.
The statement did not specify which reports it was addressing.
NetBlocks, an organisation that tracks internet outages, tweeted early Saturday that "network data show intermittent disruptions to internet connectivity in Iran."
But it said the cause was unclear and impact limited, affecting "online industrial and government platforms" and specific providers.
"Data are consistent with a cyber attack or unplanned technical incident on affected networks as opposed to a purposeful withdrawal or shutdown incident," it added.
Iran's Telecommunications Minister Mohammad Javad Azari Jahromi has acknowledged in the past that Tehran has "been facing cyber terrorism – such as Stuxnet."
The Stuxnet virus, discovered in 2010, is believed to have been engineered by Israel and the US to damage nuclear facilities in Iran.
Iran at the time accused the US and Israel of using the virus to target its centrifuges used for uranium enrichment.