Oil prices pared losses on Tuesday after President Donald Trump announced that the United States will withdraw from the 2015 Iran nuclear deal.

U.S. West Texas Intermediate crude oil settled down $1.67 a barrel, or 2.4 percent at $69.06, well off a 4.38 percent decline earlier in the day. The settlement was delayed by nearly an hour due to extremely high trading volume. The contract rose as high as $70.84 on Monday and ended the session above $70 a barrel for the first time since November 2014.

International benchmark fell 47 cents , or 0.6 percent, to $75.71, also paring back an earlier decline of 4 percent. Brent touched $76.34 on Monday, its best level since Nov. 27, 2014.

In President Trump's announcement Tuesday, he said the U.S. will withdraw from the Iran nuclear deal forged under the Obama administration and restore sanctions on Tehran suspended under the 2015 accord.

"We will be instituting the highest level of economic sanction," Trump said. "Any nation that helps Iran in its quest for nuclear weapons could also be strongly sanctioned by the United States."

Iran is OPEC's third-largest oil producer and currently exports about 2.5 million barrels a day. Renewed sanctions could crimp those shipments at a time when global oil supply and demand have essentially balanced out. That increases the risk that the market could swing into undersupply and send oil prices higher.

In a statement immediately following the president's annoucement, Treasury Secretary Steven Mnuchin said in a prepared statement that "Sanctions will be reimposed subject to certain 90 day and 180 day wind-down periods. At the conclusion of the wind-down periods, the applicable sanctions will come back into full effect."

However, prices backed off Monday's highs after Trump tweeted that he would announce his decision four days before a deadline spelled out in the nuclear deal.

The tweet convinced some investors that the worst of the market's fears — that Trump will move quickly to impose sever sanctions — won't be realized, according to John Kilduff, founding partner at energy hedge fund Again Capital. Instead, some traders are now anticipating a "Trumpian half measure," he said.

"I don't think he'll go much further than that," Kilduff said. "We're pulling out of the deal, but he's going to hold off on reimposing sanctions until he can have an opportunity to work out some other sort of arrangements with Iran and the allies themselves."

A CNN report on Tuesday appeared to at least in part confirm that expectation. Sources told the network it could take months for the sanctions to take effect as the administration develops guidelines for companies and banks.

Congressional sources told CNBC the administration plans to wind down various aspects of the deal over 90- or 180-day periods.