An Iranian ayatollah has called for the "shedding" of Donald Trump's blood in a chilling revenge statement broadcast on Iranian state television on Thursday.

Ayatollah Abdollah Javadi Amoli - amongst Iran's most senior Islamic clerics - declared the nation was "on the verge of a great test" and urged "the shedding of Zionist blood, the shedding of Trump's blood" on state television.

"Fight the oppressive America, his blood is on my shoulders," he declared, making an unusual appeal for violence from an ayatollah, amongst the highest positions in the Shiite faith.

Meanwhile, Iranian Foreign Minister Abbas Araghchi condemned the US Navy's sinking of an Iranian warship in the Indian Ocean on Tuesday night as "an atrocity at sea," killing at least 87 Iranian sailors.

"Frigate Dena, a guest of India's navy carrying almost 130 sailors, was struck in international waters without warning," he wrote on social media. "Mark my words: The US will come to bitterly regret [the] precedent it has set."

The U.S. and Israel initiated the conflict on Saturday, striking Iran's leadership, missile capabilities, and nuclear facilities, whilst indicating that removing the government could be amongst their objectives.

Israel announced multiple incoming missile attacks and air sirens sounded in Tel Aviv and Jerusalem. Iranian state television said additional strikes also targeted U.S. bases.

President Trump commended the U.S. military for "doing very well on the war front, to put it mildly."

Iran launched strikes on Bahrain, Kuwait and Israel as the situation intensified. Turkey reported NATO defences intercepted a ballistic missile fired from Iran before it could enter Turkish airspace.

The conflict has claimed more than 1,000 lives in Iran, over 70 in Lebanon and approximately a dozen in Israel, according to officials in those nations. It has disrupted global oil and gas supplies, paralysed international shipping and left hundreds of thousands of travellers stranded across the Middle East.

Nations throughout the region prepared for potential threats on Thursday, a day after Iran's paramilitary Revolutionary Guard warned of "the complete destruction of the region's military and economic infrastructure."

Qatar's Interior Ministry announced authorities were relocating residents near the U.S. Embassy in Doha as a temporary precaution, without offering further details.

This follows Trump being captured on a hot mic making an alarming threat before WW3 broke out.