Saudi Arabia has publicly accused the United Arab Emirates – a fellow Gulf Arab state and former partner in the Yemen war – of undermining its national security, an unusually blunt charge that exposes a rift long kept behind closed doors.

It comes after clashes and an independence bid in southern Yemen bring Saudi and UAE-backed forces into confrontation.

A decade after Saudi Arabia and the United Arab Emirates led a joint military campaign to curb Iran’s influence in Yemen, the two allies now find themselves pitted against each other there.