TEHRAN -- Iran's new Supreme Leader Mojtaba Khamenei on Thursday called for the continued closure of the Strait of Hormuz and pledged to open new fronts in his country's conflict with the United States and Israel.

He made the remarks in his first message published on his website since Sunday's announcement of his appointment as Iran's supreme leader.

"The demand of the masses of people is the continuation of the effective and regret-inducing defense. Also, the lever of blocking the Strait of Hormuz must definitely continue to be used," Khamenei said, addressing the country's people and armed forces.

"Studies have been conducted on the opening of other battlefronts where enemy has little experience and will be extremely vulnerable, and their activation will take place if the war situation continues and based on considering the interests," he added.

On Feb 28, Israel and the United States launched joint attacks on Tehran and several other Iranian cities, killing Iran's then Supreme Leader Ali Khamenei, along with senior military commanders and civilians. Iran responded by launching waves of missile and drone strikes targeting Israel and US bases and assets in the Middle East.

US and Israeli officials said they are preparing for at least two more weeks of strikes in Iran, with no internal directive on when fighting might stop, according to a Wednesday Axios report.