President Donald Trump said on Wednesday he has ordered new sanctions on Iran, the latest escalation in tensions between the two countries and one that follows the attack over the weekend on Saudi oil facilities that US officials have pinned on Iran.

“I have just instructed the Secretary of the Treasury to substantially increase Sanctions on the country of Iran!” Trump tweeted.

The President made the announcement as some Republican lawmakers have called for military strikes against Iran and Vice President Mike Pence has suggested a military response is possible.

But Trump, who campaigned on getting the US out of foreign entanglements, faces a battle for re-election that would be complicated by a new war. The sanctions announcement may signal his desire to avoid military conflict, analysts said.

“This is important because it appears to be Trump’s effort to respond to the Iranian attack by sanctions measures and not by military steps,” Henry Rome, an Iran analyst at the Eurasia Group, said about Trump’s Tuesday tweet. “The way I look at it, this is the substitute for a military response, not the prelude to it.”

‘Fairly marginal’

It wasn’t immediately clear to whom or which sectors the new sanctions would apply. The US has ratcheted up sanctions on the country after withdrawing last year from a multi-nation nuclear deal that constrained Iran’s nuclear activity in return for an easing of economic sanctions.

The US “maximum pressure” policy has undermined the nuclear deal, creating tensions with European allies who are trying to keep the nuclear deal afloat. The Trump administration has sanctioned all key Iranian economic sectors, including aviation and shipping. And in May, it hit the lifeblood of Tehran’s economy, sanctioning its energy exports.

Iran, unable to gain the economic benefits promised under the nuclear pact, has begun to violate certain aspects of the agreement.

Trump has yet to definitively state that Iran was behind the attack on the Saudi oil facilities, but others in his administration have pinned blame on Tehran, which has denied involvement. White House, Treasury and State Department spokespeople did not immediately provide clarity on the new sanctions.

Earlier this week, Trump appeared to preview a forceful response to the attacks, saying the US was “locked and loaded” to respond. But later he sounded less committed to a military response, telling reporters he was not interested in war.

US defense officials were ordered to plan potential responses to the attack on Saudi Arabia’s oil facilities, but the White House is waiting for the Kingdom’s rulers to decide on a response before charting a path forward, administration officials and sources familiar their thinking told CNN.

‘We’ll see’

Secretary of State Mike Pompeo was travelling to Saudi Arabia on Wednesday for meetings, and administration officials said no decision on responding to the weekend attacks was likely until he returns to Washington.

A source familiar with White House discussions said the administration feels time is on its side as it builds a case against Iran, which has denied responsibility for the attacks.

While Pompeo directly blamed Iran for the incident – which forced state-owned Saudi Aramco to halve its production – Trump has stopped short, saying he wanted to wait for a final intelligence report.

Trump has repeatedly said that the onus is on Saudi Arabia when it comes to dictating the path forward and he’s made clear he is in no rush.