An estimated 20,000 fighters involved in the Saudi-led invasion of Yemen split in half earlier this month, with half backed by the UAE and a separatist movement, and the other half Saudi-backed forces loyal to the Hadi government.

That fighting has raged, but the Saudis and UAE had talked of working something out. Thursday suggests the chances of a deal are shrinking, with the UAE getting directly involved in the fighting, and launching airstrikesagainst Saudi-backed government forces. 

The UAE confirmed its involvement in the airstrikes, saying it was engaged in self defense of its forces, as well as civilians threatened by "terrorist militias," and insisting it was in keeping with international law. 

Yemen's President Hadi, however, is angry with the "blatant aerial bombardment," and is calling for the UN Security Council to hold a session. Hadi also called on the Saudis to directly intervene militarily against the UAE.