Investing.com - Fears over possible supply constraints from the Israel-Iran conflict have driven oil prices higher in recent days, although past disruptions do not suggest that crude will stay elevated for a long time, according to analysts at Citigroup (NYSE: C ).

Brent crude futures slumped on Friday following the White House’s comments, although the contract is on course to rise for a third consecutive week.

At 08:21 ET (12:21 GMT), Brent crude futures -- the price barometer for much of the world’s oil market -- had fallen by 3.1% to $76.44 per barrel. The U.S. West Texas Intermediate crude futures for August edged lower to $73.27 per barrel.

Oil prices spiked by nearly 3% on Thursday, although trading volumes were relatively light with U.S. markets closed.

Since the beginning of the Israel-Iran fighting last Friday, oil has broadly gained, with traders fretting that the conflict could spill into the wider Middle East region and possibly disrupt crucial supply flows -- particularly in the Strait of Hormuz, which runs along Iran’s southern coast.

In a note to clients, the Citi analysts said that, while past production disruptions have been different, on average, every 1 million barrel per day of impact supply tends to "raise prompt month prices by about 15-20%."

However, these previous disruptions, which included events like the First Gulf War in 1990 and sanctions on Iran in 2012 and 2018, do not mean that prices will "go up or stay elevated for a long time," the brokerage flagged.

Price moves and production disruptions do not "necessarily line up" historically, they added.

Investors were keeping close tabs on the possible U.S. role in the air war between Israel and Iran, which has now entered its second week. President Donald Trump will decide on direct U.S. involvement in the fighting within the next two weeks, the White House said on Thursday.

Trump was seen still holding out for the possibility of nuclear talks with Tehran, even as hostilities between Israel and Iran showed little signs of cooling. While the president has publicly mused about directly attacking Iran, he has also touted the possibility of negotiations.