US Vice President Mike Pence announced that Secretary of State Mike Pompeo was on his way to Saudi Arabia to "discuss our response". This stern sentiment echoes that of the United States, who very early on claimed to be in possession of evidence that proved Tehran was the source of the attack.
Over the summer, Iran seized foreign tanker ships near the Strait of Hormuz, shot down at least one sophisticated us drone - which did not draw a military response from Trump - and began enriching nuclear materials at risky new levels.
The apparent hardening of the U.S. position came as Iran's supreme leader ruled out negotiations with Washington "at any level".
There had been reports about a possible meeting between US President Donald Trump and his Iranian counterpart, Hassan Rouhani, during the upcoming UN General Assembly this month in NY.
President Trump is "obligated to try and find peace", he said.
The sharp division in blame has placed some of the strongest US allies in the precarious position of determining how to respond to such provocative action. And if Iran did give or sell more sophisticated weapons to the Houthis, perhaps it is simply responding to the United States welching on its commitment to the nuclear deal. He says that Tehran is secretly cheating and trying to build nuclear weapons and must be stopped.
Iranian state TV quoted Ayatollah Ali Khamenei, who's been personally sanctioned by the Trump administration, as saying this is the position of the entire leadership of the country and that "all officials in the Islamic Republic unanimously believe" this.
If the current US campaign succeeds, Khameni says, Iran could then expect to face more "maximum pressure" policies from the worldwide community.
"Otherwise, no talks will happen. with the Americans", he said.
Russia detains two North Korean vessels after attack
The Trump administration has been monitoring Russian compliance with sanctions placed on North Korea over its nuclear program. Russia's relations with the reclusive North Korea are typically cordial, and the border attack is a rare incident.
Unnamed U.S. officials said satellite photos showed 19 points of impact at several facilities that they said came from the north and northwest - from the direction of Iran or Iraq - not from Huthi-held territory in Yemen.
Whether the new stage of the long-running US-Iranian standoff leads to a shooting war is the big unknown.
The United States, because of its excessive hatred of Iran, has provided key military support to Saudi Arabia for their war effort, though this support has been condemned by Congress.
Iran continues to claim that the weekend attacks were carried out using attack drones by Yemen's Houthi militias, now engaged in a brutal civil war against the Saudi- and USA -backed government.
"They can take weeks or months to get specialized parts", said Phillip Cornell, a former senior corporate planning adviser to Aramco, according to Bloomberg.
The attack was the among the most serious escalations in tensions in the Persian Gulf in recent months.
He said the USA was still investigating if Iran was behind the attacks, but added that "it's certainly looking that way at this moment".
The US military, he said, was working with its partners to "address this unprecedented attack". "Certainly, when there is a spike in prices, it creates anxiety", he told reporters here. Saudi Arabia, which has supported tougher USA sanctions on Iran, said an initial investigation showed the strikes were carried out with Iranian weapons. "I think the market will be reacting on the situation based on the information that will be coming out from Saudi Arabia", Novak said.
The assault halved Saudi Arabia's oil output and damaged the world's biggest crude oil processing plant, triggering the largest jump in oil prices in decades. The Houthis have used their drones in attacks this way in the past, with one captured on video in January exploding over a crowd at a military parade.