Oil prices extended gains on Tuesday as U.S. President Donald Trump heightened his rhetoric ​against Iran, threatening stronger action if the country fails to reopen the Strait of Hormuz, a key global ‌oil transit chokepoint.

Brent crude futures rose 57 cents, or 0.5%, to $110.34 a barrel by 1202 GMT, while U.S. West Texas Intermediate crude futures were up $1.26, or 1.1%, at $113.67.

Trump has threatened to rain "hell" on Tehran if it fails to comply with his deadline of 8 p.m. EDT Tuesday to reopen ​the strait. "They could be taken out," Trump warned, pledging further action if a deal is not reached.

Responding to a ​U.S. proposal through mediator Pakistan, Tehran rejected a ceasefire and said a permanent end to the ⁠war was necessary, and pushed back against pressure to reopen the strait.

Iranian forces effectively shut the Strait of Hormuz after ​U.S. and Israeli attacks began on February 28, disrupting a waterway that typically carries about 20% of global oil flows.

"Clock-watching is now playing almost as ​big a role in oil markets as the fundamentals themselves in the run-up to Trump's ultimatum deadline," said Tim Waterer, chief market analyst at KCM Trade.

"The potential for a ceasefire deal offers some counterweight and could spark a relief move lower if it gains traction, but persistent supply ​worries from the Hormuz chokepoint and damaged energy facilities are keeping the floor under prices."

On Monday, Iran's Revolutionary Guards halted two ​Qatar liquefied natural gas tankers and directed them to hold position without providing explanations, sources told Reuters. However, shipping data has shown limited vessel movement through ‌the strait ⁠since last Thursday.

The U.N. Security Council is expected to vote on Tuesday on a resolution to protect commercial shipping in the Strait of Hormuz, but in significantly watered-down form after veto-wielding China opposed authorizing force, diplomats said.

The attack in the region continued as explosions were heard in the Syrian capital, Damascus, and surrounding countryside on Tuesday that were caused by the Israeli interception of ​Iranian missiles, Syrian state TV reported.

Saudi ​Arabia said on Tuesday it intercepted ⁠and destroyed seven ballistic missiles launched towards its Eastern Region, with debris falling near energy facilities, according to the defence ministry.

The conflict has pressured global crude markets, with spot premiums for U.S. ​WTI crude surging to record highs as Asian and European refiners scramble to secure replacement ​supplies amid disrupted ⁠Middle Eastern flows.

Saudi Arabia's state oil company Aramco raised the official selling price of its Arab Light crude to Asia for May delivery, setting a record premium of $19.50 a barrel above the Oman/Dubai average.

Adding to supply concerns, Russia on Monday said Ukrainian drones attacked the Caspian ⁠Pipeline Consortium's ​terminal on the Black Sea, which handles 1.5% of global oil supply. Russia ​reported damage to loading infrastructure and storage tanks.

OPEC+ agreed on Sunday to lift oil output quotas by 206,000 bpd in May, though the increase will be largely ​notional as key members cannot boost production because strait closures are curbing exports.