The Trump administration and its allies in Congress presented a shifting new justification Monday for the U.S. attack on Iran, with House Speaker Mike Johnson suggesting that the White House believed Israel was determined to act on its own, leaving the president with a “very difficult decision.”

Johnson said the attack on Iran was a “defensive operation” because Israel was ready to act against Iran, “with or without American support.” He said President Donald Trump and his team determined that Iran would immediately retaliate against U.S. personnel and assets.

The remarkable shift in the Trump administration’s stated rationale comes as the hostilities deepen and widen across the region. The president himself estimated the war could drag on for weeks. The administration plans to seek supplemental funds from Congress to support the effort.