This is bad news for Saudi Arabia and a sign of a growing split among US allies in the Middle East.

• The UAE, despite being close to the US and Israel, is secretly giving intelligence and targeting help to the Houthis, who are backed by Iran, in their fight against Saudi-backed forces inside Yemen.
• The help reportedly does not extend to Houthi attacks inside Saudi Arabia itself, only the fight within Yemen.
• The US has learned about this and privately told the UAE to stop, but the help has reportedly continued anyway.
• The UAE's goal seems to be regaining influence in southern Yemen after being pushed out by the Saudis, not building a lasting partnership with the Houthis.
• Both the UAE and the Houthis publicly deny any alliance, but sources say the cooperation is real and tied to lingering resentment from the UAE getting shoved aside by Saudi Arabia.

Outlook: Expect continued denials from both sides while fighting in Yemen keeps going, with little sign the US will intervene more heavily despite the strain this puts on its alliance with Saudi Arabia.