LONDON, March 1 (Xinhua) -- The military strike against Iran will "take four weeks -- or less," U.S. President Donald Trump said in an exclusive phone interview with Britain's Daily Mail, the newspaper reported Sunday.

The Daily Mail said Trump "broke his silence" on the first U.S. casualties in the conflict. Three U.S. soldiers were killed in action and five others seriously injured as part of the military operation against Iran, the U.S. Central Command said Sunday.

Trump acknowledged the deaths were the first casualties of his second term, the report said.

On the potential duration of the war, Trump suggested the fighting could continue for weeks. "It's always been a four week process. We figured it will be four weeks or so. It's always been about a four week process so -- as strong as it is, it's a big country, it'll take four weeks -- or less," he said.

Trump told the Daily Mail he was not surprised by the outcomes of the strikes so far.

The U.S. president also said he had spoken Sunday with the leaders of Bahrain, Saudi Arabia, the United Arab Emirates, Qatar, Jordan and a "couple of others."

The United States and Israel on Saturday launched "major combat operations" against Iran. Iran's state media confirmed Sunday that Supreme Leader Ayatollah Ali Khamenei was killed in the attacks. ■