"The investigation is continuing and all indications are that weapons used in both attacks came from Iran," coalition spokesman Turki al-Maliki told reporters.
Russia, however, warned against blaming Tehran.
"We consider it counterproductive to use what has happened to stir up emotions regarding Iran in line with the well-known rhetoric of the United States," Russia's Foreign Ministry said, pointing out that Houthi rebels had claimed responsibility for the attacks.
The strikes resulted in major fires at two key oil facilities. Iran dismissed US claims it was behind the attacks as "unacceptable."
In response, US President Donald Trump tweeted: "We'll see?"
US Defense Secretary Mark Esper also once more pointed the finger at Tehran, calling the recent attack "unprecedented" and saying that the US was working with its allies to defend the "international rules-based order that is being undermined by Iran." He also said that he had spoken with Saudi Arabia's crown prince and the Iraqi defense minister over the weekend.
German weapons banMeanwhile a lawmaker in German Chancellor Angela Merkel's party says Germany should reconsider its ban on arms exports to Saudi Arabia.
Juergen Hardt, parliamentary foreign policy spokesman for the Christian Democrats, told newspapers of the Redaktionsnetzwerk Deutschland that "a lifting of the export ban on defensive weapons systems is in our strategic interest" to help Saudi Arabia protect itself.
Russian President Vladimir Putin on Monday offered to sell Saudi Arabia air defense weapons to protect against attacks, notably the S-300 surface-to-air missile system and its successor, the S-400.
'Act of terror'An economist from Norway — one of the world's largest oil and gas exporters — said the attacks could unleash a series of events that would hit the country's economy hard.
Norway is "completely dependent on trade with the outside world," said Oeystein Doerum, chief economist with the Confederation of Norwegian Enterprise.
Doerum told the Norwegian news agency NTB that "it is positive when oil prices rise as a result of an increased demand but not when it is the consequence of a terrorist attack."
India also condemned Saturday's attack as an act of terrorism.
Raveesh Kumar, India's External Affairs Ministry spokesman, said India vowed to "oppose terrorism in all its forms and manifestations."
But China’s Foreign Minstry spokeswoman, Hua Chunying, warned against jumping to conclusions. She said that "given the absence of a conclusive investigation and result, I think it is irresponsible to determine who should assume responsibility for it."
Read more: Iran-US tensions flare in the Persian Gulf: What's at stake?
kw/rt (AP, dpa, Reuters)
DW sends out a daily selection of the day's news and features. Sign up here.