New Delhi, Jan. 1 -- Saudi Arabia bombed Yemen's port city of Mukalla on Tuesday, targeting a shipment of weapons from the United Arab Emirates for separatist forces - a significant move in a country located along a key international trade route that threatens to bring new risks to the Persian Gulf region. The UAE later said it would withdraw its forces from Yemen.

The secessionist Southern Transitional Council, STC, a group backed by the United Arab Emirates, this month seized most of the the provinces of Hadramout and Mahra, including oil facilities.

Yemen has been mired for more than a decade in a civil war that involves a complex interplay of sectarian grievances and the involvement of regional powers.

The Iran-aligned Houthis cont...