Washington (CNN) President Donald Trump told reporters Monday that "it's looking like" Iran was behind this weekend's attack on oil facilities in Saudi Arabia but suggested it was too early to say for sure. He also said he was "not looking to get into new conflict, but sometimes you have to."

"Well, it's looking that way," Trump said in the Oval Office when asked if Iran was responsible. "We'll let you know definitively. ... That's being checked out right now."

Trump also insisted that he does not want war with Iran, but he noted the US has the best weapons systems, namely fighter jets and missiles.

"The United States is more prepared" for a conflict than any country in history, he said. "With all that being said, we'd certainly like to avoid it."

Trump indicated that the Saudis may have to pay if the US launches military action.

"The Saudis are going to have a lot of involvement in this if we decide to do something. They'll be very much involved, and that includes payment," he said.

The President also left the door open for diplomacy with Iran, saying that path has not yet been exhausted.

"No, it's never exhausted. ... You never know what's going to happen. ... I know they want to make a deal. ... At some point it will work out," he said.

Asked if he has promised the Saudis he will protect them, Trump said: "No, I haven't promised the Saudis that."

"We have to sit down with the Saudis and work something out," he added.

Trump's special representative for Iran, Brian Hook, held a call with staffers from Capitol Hill on Monday to discuss the attacks, according to four sources familiar with the call.

During that conversation, Hook said the attack was definitely not carried out by Houthi rebels, who have claimed responsibility, and was not launched from Iraqi soil. However, Hook wouldn't say who did carry out the attack when pressed, one source familiar told CNN.

Hook also said the Saudis view this attack as "their 9/11," two sources said, referring to the terrorist attacks on US soil on on September 11, 2001.

Both sources said that they felt Hook's comment was inappropriate, in part because there have been no reported deaths as a result of the Saudi oil field strikes yet nearly 3,000 Americans were killed in New York, Washington and outside of Shanksville, Pennsylvania, in the 9/11 attacks.

'It's one thing to tell us, it is another thing to show us'

Trump's comments come after CNN reported the US has told at least one ally in the Middle East that it has intelligence showing that the weapons launch "likely" came from staging grounds in Iran but has not shared that intelligence yet.

"It is one thing to tell us, it is another thing to show us," a diplomat from the region said Monday.

A US official separately told CNN that the US has assessed that the attack originated from inside Iran. The official spoke on condition of anonymity because they are not authorized to talk to the press.

Still, US officials have not offered any evidence proving Iran was behind the attack or that the strike originated from Iranian territory.

The Pentagon declined to comment. The White House did not respond to a request for comment. A State Department spokesperson told CNN: "We do not comment on intelligence matters."

The Wall Street Journal first reported that the US was telling countries in the region that the attacks were launched from inside Iran.

A spokesman for the Saudi-led coalition in Yemen, Col. Turki al-Malki, said in a news conference Monday that Iranian weapons were also used in the oil field attack and that the strikes were not launched from Yemen, despite claims of responsibility by Houthi rebels operating there.

"All practical evidence and indicators and the weapons used in both attacks show preliminarily that these are Iranian weapons," he said, without providing details about the weapons themselves.

Yemen's Iran-backed Houthi rebels claimed responsibility on Saturday, saying they had conducted the strikes -- using 10 drones -- in retaliation for Saudi Arabia's military campaign against the group in the country.

While the Houthis have used attack drones in the past, those attacks have typically been launched against Saudi targets close to the border. The recent attack against Saudi oil facilities would represent a major improvement in the Houthis' ability to accurately hit targets at a much greater distance than previously demonstrated.

Al-Malki said Saudi Arabia is still working on identifying the exact launch location but noted that "all the preliminary evidence indicates that the terror attack was not launched from Yemeni territory as claimed by the Houthi militias."

"These militias are just a tool in the hands of the Iranian revolutionary guards used to implement the agenda and wishes of the revolutionary guards and the Iranian terrorist regime," the colonel added.

On Sunday, Trump tweeted that the US has "reason to believe that we know" who is responsible for an attack on a Saudi Arabian oil field and the country is "locked and loaded depending on verification" following the crippling strike.

Though Trump did not name Iran in his tweet, the attack has caused another spike in tensions between the US and Tehran. Prior to Saturday there had been signs that the US appeared open to new negotiations and even a potential meeting later this month between Trump and Iranian President Hassan Rouhani.

Iran denies involvement

On Saturday, Iranian Foreign Ministry spokesman Seyyed Abbas Mousavi rejected the accusation that Iran was behind the attack.

"Such blind accusations and inappropriate comments in a diplomatic context are incomprehensible and meaningless," he said, adding, "Even hostility needs a certain degree of credibility and reasonable frameworks, US officials have also violated these basic principles."

Marc Short, the vice president's chief of staff, told reporters Monday morning that the President's claim the US is "locked and loaded" may not refer to military action.

"I think that 'locked and loaded' is a broad term and talks about the realities that we're all far safer and more secure domestically from energy independence," Short said. "This is not the 1970s oil embargo. It's not 1990, when Iraq invaded Kuwait. We're now a net oil exporter, which means that the American market is much better protected."

Secretary of State Mike Pompeo has explicitly blamed Iran for the attack but has also yet to offer any evidence to support that claim. Pompeo and other administration officials will soon travel to Saudi Arabia, according to Trump.

Kelly Craft, the US ambassador to the United Nations, reiterated that assertion Monday while addressing the attacks during an unrelated Security Council meeting on Yemen.

"Claims of responsibility have been made, but as Secretary of State Mike Pompeo has clearly stated, there is no evidence that the attacks came from Yemen. Emerging information indicates that responsibility lies with Iran," she said.

Short told reporters Monday he's "quite confident" that Pompeo will release evidence that "directly ties these attacks to Iran."

"There's no doubt that Iran has been a malign actor on the stage here and has been supporting the Houthi rebels in Yemen, but I think there's certainly greater evidence that he'll be sharing that directly ties these attacks to Iran," he said.

The claim is reminiscent of when Pompeo blamed Iran for an attack on two tankers in the Gulf of Oman earlier this summer, without presenting evidence directly tying Iran to the attacks.

What countries in the region decide to do in reaction to the Saudi oil field attack largely depends on what the US is willing to do, a US official said. CNN previously reported that Pompeo is expected to speak with the United Arab Emirates Crown Prince on Monday and to other nations.