Turkish President Recep Tayyip Erdogan lobbed a rare direct attack at the emirate of Abu Dhabi over its backing of Khalifa Haftar and the Russian mercenaries fighting on his behalf in Libya.

Abu Dhabi pays for thousands of Russian mercenaries who fight alongside the Libyan general’s forces, which are violating a recent cease-fire brokered by global powers, Erdogan said during a visit to three African states on Monday.

The Turkish president’s remarks came shortly after Libya’s internationally recognized government in Tripoli said repeated attacks by Haftar’s forces have rendered a recent truce all but meaningless. A conference convened by Germany had sought a cessation of hostilities to pave the way for an end to the civil war in the North African country.

Read more: bloomberg