BEIJING, July 9 (Reuters) - Oil prices rose on Thursday after the United States launched fresh strikes against Iran, dimming hopes of ending the war and fully reopening the Strait of Hormuz.

By 0054 GMT, Brent crude futures had risen 78 cents, or 1%, to $78.80 a barrel. U.S. West Texas Intermediate crude futures were up 74 cents, or 1.01%, at $74.26 a barrel.

Both crude oil benchmarks rose by more than a dollar in post-settlement trading on Wednesday after the U.S. military began launching new strikes on Iran.

Prior to that, the two benchmark crude oils reached their highest levels in more than two weeks at settlement after US President Donald Trump threatened to bomb Iran last night.

The US military said it carried out new strikes on Iran to keep the vital Strait of Hormuz open to shipping, hours after Trump said the interim agreement to end the war was "over".

Tony Sycamore, an analyst at IG, said in a note that the flow of oil through the strait in the past few weeks has stopped for the time being, and ship owners are expected to take a more cautious stance.

The United States said its latest round of attacks was in response to the targeting of three tankers transiting the Strait of Hormuz on Tuesday. The US strikes hit several cities along Iran's southern coast and caused power outages in some areas.

Iran said on Wednesday that it had attacked US military sites in Bahrain and Kuwait in retaliation for earlier US strikes targeting infrastructure.

Insurance industry sources reported on Wednesday that war risk insurers have advised shipping companies to suspend their voyages through the Strait of Hormuz, while others are reviewing the terms of their insurance policies following renewed Iranian attacks on ships.