Most Asia-Pacific markets were set to open lower on Tuesday, as the conflict in Iran continues to rage on for a fourth day. Oil prices extended gains after Iran reportedly said it had closed the Strait of Hormuz, with U.S. crude futures up 0.15% to $71.33, while Brent was up 7.14% to trade at $78.07 per barrel. More than 14 million barrels per day transited via the Strait on average last year, accounting for nearly a third of the world's overall seaborne crude exports, according to Kpler data.