By Mohammed Ghobari and Jana Choukeir

DUBAI, Sept 21 (Reuters) - Houthi fighters pushed to seize strategic heights in Yemen on Monday to cut off the Red Sea coast from remaining areas held by Saudi-backed forces, after a report that President Donald Trump had called off US strikes on the group at the last minute.

A lightning advance by the Iran-backed ‌group this month has extended the wider Middle East conflict to a new theatre and further threatened global energy supplies.

Washington has so far rebuffed repeated pleas from Saudi Arabia's Crown ‌Prince Mohammed bin Salman to join the fight in Yemen. The Houthis said on Saturday they had fired on Riyadh, where loud booms were followed by columns of smoke visible near the airport.

Saudi Arabia has not commented on the first apparent strikes on ​the capital since the escalation began.

The New York Times reported that the Trump ...