Since Israel began its concerted attack on Iran on Friday, calls for regime change in Iran have grown louder – from hawks in the US Congress to Israeli officials and some Iranian activists abroad.

Iran fired a new wave of missile attacks on Israel early Monday, triggering air raid sirens across the country as emergency services reported at least five killed and dozens more wounded in the fourth day of a conflict between the regional foes that showed no sign of slowing.

A White House official said President Trump had decided not to sign onto a statement drafted for Group of 7 allies that urges restraint from both Israel and Iran, which have been trading attacks for days.

European foreign ministers told their Iranian counterpart in a call on Monday to return to nuclear negotiations with the U.S. and refrain from escalating conflict with Israel, to which Iran's foreign minister said Tehran's priority was to confront Israel for now,

Iranian officials have warned that U.S. participation in an attack on its facilities will imperil any chance of the nuclear disarmament deal the president insists he is still interested in pursuing.

U.S. refueling aircraft and warships have been dispatched to safeguard U.S. interests as the deadly conflict shows no sign of abating.

President Donald Trump on Sunday issued a stark warning to Iran against retaliating on U.S. targets in the Middle East while also predicting Israel and Iran would “soon” make a deal to end their escalating conflict.