Johansson flashes ring, but not fiance

Newly engaged Scarlett Johansson flashed a sparkling diamond engagement ring, but not her new fiance at Monday night's Costume Institute Gala in New York.

Just hours after the actress confirmed her engagement to Canadian star Ryan Reynolds; Johansson, 23, took to the red carpet at the city's Metropolitan Museum of Art - alongside a galaxy of stars including Kate Moss, Tom Cruise and Katie Holmes, Julia Roberts and George Clooney.