Global crude prices rose more than 1% on Wednesday and were trading near a three-week high hit during the session, as investors worried about escalating tensions in the Middle East after the United Arab Emirates decided to suspend all financial and economic transactions with Iran.

Shipping through the Strait of Hormuz also remained slow, data showed, as most ship owners avoided the waterway because of a lack of clear signalling on its reopening from a blockade. Brent crude futures were up $1.17, or nearly 1.3%, at $92.21 at 1741 GMT. US WTI crude futures were $1.51, or 1.8% higher at $86.45 a barrel.

“Crude futures remain supported by the geopolitical tensions that remain in the Middle East, now with the UAE stating they have cut off all financial ties to Iran due to the latest missile attacks,” said Dennis Kissler, senior vice president of trading at BOK Financial.