Oil prices were down on Monday after rising during the previous session as civil unrest in Iran subsided, lowering the chance of a US attack that could disrupt supply from the major Middle Eastern producer.
Brent crude was trading at $63.85 a barrel at 0734 GMT, down 28 cents or 0.44%.
US West Texas Intermediate for February fell 36 cents, or 0.61%, to $59.08 a barrel. That contract expires on Tuesday and the more active March contract was at $59.10, down 24 cents, or 0.40%.
Iran's violent crackdown on protests spurred by economic hardship, which officials say killed 5,000 people, quelled the unrest, reported Reuters.
US President Donald Trump seemed to step back from his earlier threats of intervention, saying on social media Iran had called off mass hangings of protesters, although the country had not announced any such plans.
That appeared to lower the odds of a US intervention that could have disrupted oil flows from the fourth-largest producer among the Organization of the Petroleum Exporting Countries.
The downturn signaled a renewed retreat from multi-month highs reached last week, although prices still settled higher on Friday.
"The pullback followed a swift unwind of the 'Iran premium' that had driven prices to 12-week highs, triggered by signs of easing in Iran's crackdown on protesters," IG market analyst Tony Sycamore said in a note.
That was accentuated by US inventory data showing a substantial crude build and reinforcing bearish supply pressures, he added.
US markets are closed on Monday for Martin Luther King Jr. Day.
Crude stocks were up by 3.4 million barrels in the week ended January 9, the EIA said last week, versus analysts' expectations in a Reuters poll for a 1.7 million-barrel draw.
Markets are closely watching plans for Venezuela's oil fields, after Trump said the United States would run its oil industry after the capture of Nicolas Maduro.
The United States is moving as fast as possible to grant Chevron an expanded production license in the country, the US energy secretary told Reuters on Friday.
But markets were less confident about the prospects for scaled-up Venezuelan production.
"Venezuela and Ukraine remain on the back burner," said Vandana Hari, founder of oil market analysis provider Vanda Insights.
"Expect rangebound movement for the rest of the day, with US markets closed."
China's refinery throughput in 2025 rose 4.1% year on year, while crude oil output grew 1.5% from 2024, with both reaching all-time highs, government data showed on Monday.
