The U.S. President declared a 3-week-long cease-fire with Iran dead after fighting flared overnight amid escalation sparked by Iranian attacks on ships.

Any renewed attacks would follow strikes by both the U.S. and Iran following the downing of a U.S. helicopter.

The US military launched a new round of strikes against Iran on Wednesday, following President Donald Trump's assertion that the fragile ceasefire between the two countries was over. Trump warned that the attacks could get "much worse" if Iran perpetrated further attacks on ships in the Strait of Hormuz.

The American military said it hit around 90 targets in airstrikes across Iran and Tehran retaliated with attacks on three Gulf states overnight into Thursday.

The United States launched a fresh wave of military strikes against Iran on Wednesday, targeting what it described as Tehran's ability to threaten shipping through the strategically vital Strait of Hormuz.

The U.S. began a second night of strikes Wednesday and Iran responded in kind after President Trump declared earlier in the day that the ceasefire was "over."

President Donald Trump said the US would probably launch further strikes on Iran and could resume a blockade on the country’s ports, ratcheting up pressure on Tehran and raising the prospect of a return to all-out war.

Iranian officials say U.S. strikes have rendered the ceasefire "meaningless" Thursday as peace talks have made little progress.