Oil prices climbed above $100 a barrel on Wednesday for the first time since July as rising tensions in the Middle East fueled concerns over a fresh disruption to global crude supplies.

Brent crude, the international benchmark, rose 2.1 percent to slightly above $100 a barrel, crossing the $100 mark for the first time since July 24.

The latest increase came as the United States and Iran stepped up attacks involving shipping in and around the Strait of Hormuz. US forces said they had destroyed five Iranian crude oil tankers on Tuesday following attacks by Iran’s Islamic Revolutionary Guard Corps on a US warship.

Iran responded on Wednesday by saying it had attacked two US vessels and eight oil tankers, while its Revolutionary Guards said several ships attempting to cross what it described as a prohibited and unsafe area of the Strait of Hormuz had also been targeted.

Iran also reported ballistic missile strikes on a US air base in Jordan, adding to concerns that the war could spread further across the region. The escalation has raised fears of another supply crunch in global oil markets, particularly as countries continue drawing down their strategic reserves.

Oil prices had reached $126 a barrel in late April during the peak of the US-Iran war before falling to around $70 following a ceasefire agreement in early July.

However, crude prices have risen steadily over the past six weeks as attacks on shipping continued and expectations for a quick end to the war weakened.