The United States Donald Trump on Wednesday said the United States would strike Iran “extremely hard” within the next two to three weeks.

“We’re going to hit them extremely hard over the next two to three weeks,” he said, in a national address on Wednesday.

“We’re going to bring them back to the stone ages, where they belong.”

Shortly after his 19-minute speech, Asian markets erased earlier gains from Thursday’s session, with benchmarks in Australia, Japan and South Korea turning lower.

South Korea’s Kospi tumbled 5.5 per cent, leading regional losses.

Markets in Hong Kong and mainland China, which opened soon after the address, also began the day in negative territory.

Oil prices reacted sharply after Trump’s speech, with Brent crude futures surging 6.7 per cent to $107.92 per barrel and U.S. West Texas Intermediate rising 6.2 per cent to $106.39.

Although Trump stated that the U.S. has nearly achieved its objectives, analysts warned that his threat to strike Iran “extremely hard” could continue to push oil prices higher.

On Wednesday morning, Donald Trump claimed on Truth Social that Iran’s “New Regime President” had asked the United States for a ceasefire, saying Washington would only “consider” it once the Strait of Hormuz was “open, free and clear.

Iran’s government has denied that any such request was made, calling Trump’s statement “false and baseless.