Concerns have grown over the impact of the ongoing tensions in the Middle East on the global economy as oil prices hit $100 per barrel for the first time since July.

A barrel of Brent crude, which remains the international benchmark, has risen since last week and may rise above the $100 amid the war.

The Brent crude on Wednesday rose 2.3% to briefly trade at $100 per barrel before falling back slightly.

The United States crude oil, however, were up 1.3% to hit $94 per barrel.

The price surge came after a day of conflict and war developments with the U.S. striking Iranian oil tankers and Iran-backed Houthis attacking Saudi Arabia.

Amid the escalating tensions, oil prices have been oscillating as traders continue to react to monitor oil tanker traffic through the Strait of Hormuz.

The U.S. Central Command on Tuesday said it struck four Iranian tankers in the Gulf of Oman and one near Kharg Island as a retaliation for an attempted ballistic missile attacks on a U.S. Navy warship.

Iran attacked U.S. targets in the Middle East on Wednesday in retaliation for the American strikes on their oil tankers.

Tehran’s powerful Revolutionary Guards said they attacked 20 U.S. vessels trying to pass through the Strait of Hormuz, a vital waterway for the world’s oil and gas.

Since the U.S.-Iran war stated in February, oil prices have remained unstable globally, as the closure of Strait of Hormuz continues to hamper the global supply of liquified natural gas.