President Donald Trump on Wednesday pledged to "substantially increase" sanctions on Iran as tensions in the Middle East continue to rise following an attack on a Saudi oil field.

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

Trump's tweet came as U.S. Secretary of State Mike Pompeo was headed to Saudi Arabia to meet with Crown Prince Mohammed bin Salman to discuss the recent attack on the kingdom's oil facilities, an action American officials believe originated from Iranian territory.

Later Wednesday, Trump told reporters in Los Angeles that his administration will "be adding some very significant sanctions" on Iran within the next two days.

NBC News reported Tuesday that the administration was weighing a range of options to retaliate against Iran, including a cyberattack or physical strikes, U.S. officials briefed on recent deliberations said. Military leaders presented Trump with multiple possible actions in a national security meeting Monday, but Trump asked for additional choices, people briefed on that meeting said.

Iranian President Hassan Rouhani said Saudi Arabia should see the attack on its oil facilities as a warning to end the war in Yemen, while insisting the attack came from Yemeni forces.

The president tweeted over the weekend that the U.S. was "locked and loaded" in preparation for some sort of retaliatory action in response to the oil field attack.

"Saudi Arabia oil supply was attacked," he tweeted Sunday. 'There is reason to believe that we know the culprit, are locked and loaded depending on verification, but are waiting to hear from the Kingdom as to who they believe was the cause of this attack, and under what terms we would proceed!

Speaking with reporters in the Oval Office on Monday, however, Trump said he doesn't "want war with anybody."

"I'm somebody that would like not to have war," he added, saying that the U.S. has "to sit down with the Saudis and work something out."

The president has ratcheted up economic sanctions on Iran after withdrawing from the Iran nuclear deal last year. Previous sanctions have targeted Iranian oil, its automotive and civil aviation industries and the trade of gold and other metals.

While a number of GOP lawmakers applauded Trump for his decision to impose further sanctions on Iran, other Republicans appeared split.

Sen. Lindsey Graham, R-S.C., suggested to reporters Wednesday that sanctions won't send a strong enough message.

"I am looking for a response that will be unequivocal. If they don't pay a price for bombing a neighbor's oil fields then all hell is going to break loose in the Mideast," Graham said. "I appreciate building a coalition, I think that's smart, I'm not looking for a response immediately, but I am looking for a response that would restore deterrence and my belief is that additional sanctions will fall short."

Sen. Mitt Romney, R-Utah, meanwhile, told reporters Wednesday that while he has seen intelligence and believes Iran was behind the attacks on Saudi oil facilities, the kingdom must be the one to respond.

"This is up to Saudi Arabia,” he said. “We've been selling them weapons over the years, so they're able to defend themselves. But we're not the policemen of the world, and if Iran attacks Saudi Arabia, Saudi Arabia should be the nation that decides exactly how they're going to respond.”