By Janet H. Cho

Stock futures were falling on Sunday and oil prices spiked after tensions flared up between the U.S. and Iran even as the two sides met in Switzerland to hammer out a permanent peace deal.

On Saturday Iran said the Strait of Hormuz was closed again, and President Donald Trump answered back with renewed threats to bomb Iran.

Just after 6 p.m. Eastern time on Sunday, Dow Jones Industrial Average futures were down 0.3%, while Nasdaq 100 futures were down 0.4%, and S&P 500 futures were down 0.3%. WTI continuous contract oil rose 2.7% to about $78 a barrel.

Oil prices had fallen last week after a temporary 60-day peace framework was reached and signed. The price of Brent continuous contract oil was down 0.2% at $80.36 a barrel on Friday. WTI continuous contract was up 0.9% at $76.54 a barrel.

Gasoline prices were averaging $3.938 a gallon on Sunday, down from $4.074 a gallon last week, and $4.564 a gallon last month, according to AAA.

Energy Secretary Chris Wright told ABC News' This Week that oil and gas prices "will continue to head down." He said that the U.S. has been escorting ships through a southern route through the strait, and that flows of oil and natural gas through the Strait of Hormuz "have already returned to normal and they will continue that way."

Trump on Sunday morning said that if Iran doesn't stop Hezbollah from "causing trouble," referring to "highly paid PROXIES in Lebanon," the U.S. would "hit Iran very hard again, just like we did last week, only harder!!"

He posted it on social media just as U.S. negotiators led by Vice President JD Vance were meeting with Iranian counterparts in Switzerland to hammer out a permanent peace deal.

Iran said Saturday that it was closing traffic through the Strait of Hormuz because of Israel's attacks on Lebanon. That prompted Trump to warn on that if Iran closed the Strait, they "won't have a country."

Diplomatic tensions have renewed as a new poll by AP-NORC found that two-thirds of Americans disapprove of how Trump is navigating issues with Iran, 53% said American military action against Iran had gone too far, and only 34% approve of how Trump is handling Israel.

All three major U.S. stock indexes ended last week with gains.

The Dow Jones Industrial Average closed up 0.7%, in the largest one-week point and percentage gain since the week ended May 29, according to Dow Jones Market Data.

The Dow is up 7.3% this year.

The S&P 500 ended the week up 0.9%, also its largest one-week point and percentage gain since the week ending May 29.

The S&P 500 is up 9.6% year to date.

The tech-heavy Nasdaq Composite closed up 2.4%, posting its largest one-week point and percentage gain since the week ended May 8.

The Nasdaq is up 14.1% this year.

Write to Janet H. Cho at janet.cho@dowjones.com

This content was created by Barron's, which is operated by Dow Jones & Co. Barron's is published independently from Dow Jones Newswires and The Wall Street Journal.

(END) Dow Jones Newswires

June 21, 2026 18:13 ET (22:13 GMT)

Copyright (c) 2026 Dow Jones & Company, Inc.