Brent crude could surge to $200 a barrel, pushing U.S. gasoline prices to around $7 a gallon, if the Iran conflict drags on through the end of June and the Strait of Hormuz remains largely closed to shipping traffic, Macquarie strategists warned in a note.

These fears were echoed by Egyptian President Abdel Fattah al-Sisi, who warned at an energy conference in Cairo that supply disruptions and rising prices could push oil above $200 per barrel, calling such projections realistic rather than exaggerated.

Oil prices rose on Monday after Yemen’s Houthi group attacked Israel over the weekend, pointing to a broader scope for the war in the Middle East as the conflict enters its second month. 

Continued hostilities between Iran and the joint forces of the U.S. and Israel also showed few signs of de-escalation, with Tehran stating that it was prepared for a U.S. ground invasion as Washington deployed more troops to the Middle East. 

The U.S. dollar firmed on Monday, as investors sought the relative safety of the currency amid an unclear trajectory for the Iran war.

By 08:31 ET (12:31 GMT), the U.S. dollar index, which track the greenback against a basket of currency peers, had risen by 0.2% to 100.34. The euro fell by 0.2% to $1.1483, while the British pound had declined by 0.2% to $1.3232.

 Gold prices gained on Friday and were set for a weekly advance, as investors shunned risky assets and moved into safe haven areas such as bullion and the dollar. Uncertainty over peace talks between the U.S. and Iran and escalating fighting have battered sentiment.

Spot gold added 2.6% to settle at $4,492.74/oz. Gold Futures advanced 2.5% to settle at $4,520.40/oz.