Reporting from Washington, Al Jazeera’s Alan Fisher says Trump and Secretary of State Marco Rubio have spoken in the past 24 hours about multiple waves of US attacks, with a third wave described as the biggest yet — and still to come.

Fisher said this aligns with comments earlier this week from Gen Dan Caine, chairman of the Joint Chiefs of Staff, who indicated the US was still moving additional military assets into the region.

The continued build-up, Fisher added, suggests the US may have begun strikes before its full regional posture was in place — with more ships, aircraft and troops still being repositioned ahead of further operations.