Spencer Pratt and Heidi Montag let the world know they were feuding on "The Hills" on Monday night, and the feud has continued and moved on to Las Vegas. The two are in Vegas filming for their show, but are staying in separate rooms, and in fact separate hotels.

Pratt has checked into the Hard Rock while Montag is staying at the Palazzo. Montag told Pratt on Monday's show that she needed space, and she still appears to need it. The on-again, off-again couple seems to definitely be off. While working in Vegas the two could be seen arguing for the cameras at the Palazzo's Dos Caminos restaurant.