The dramatic escalation in tensions between Israel and Iran caused a spike in the price of crude and raised fears among oil traders about disruption to shipping in the Strait of Hormuz, one of the world’s most vital waterways.

Oil prices are fluctuating as the conflict between Iran and Israel continues for the sixth straight day. Brent crude had reached $76.70 per barrel, its highest level since February, while West Texas Intermediate (WTI) was also trending up.

Oil prices rose after Israel and Iran continued their attacks on each other over the weekend. The market is preparing for an escalation that could disrupt supplies from the region, which accounts for about a third of global crude oil production,