Natalie Portman, Colin Firth, Christian Bale and Melissa Leo to present at Oscars

(CBS) Last year's Academy Awards acting winners are set to grace the Oscar stage once again - this time, as presenters.

Colin Firth, Natalie Portman, Christian Bale and Melissa Leo have been added to the list of presenters at Sunday's ceremony, it was announced Thursday.

Pictures: Oscar nominees 2012

Complete Coverage: The 84th Academy Awards

Bale and Leo received supporting actor and actress honors for their roles in "The Fighter." Firth won the best actor Oscar for his work in "The King's Speech," while Portman took best actress for her role in "Black Swan."

The quartet joins a list of previously-announced presenters that include Halle Berry, Rose Byrne, Bradley Cooper, Tom Cruise, Penelope Cruz, Cameron Diaz, Michael Douglas, Will Ferrell, Tina Fey, Zach Galifianakis, Tom Hanks, Angelina Jolie, Milla Jovovich, Ellie Kemper, Jennifer Lopez, Melissa McCarthy, Wendi McLendon-Covey, Maya Rudolph, Emma Stone, Meryl Streep and Kristen Wiig.

The 84th Academy Awards ceremony will be broadcast Sunday on ABC beginning at 7 p.m. ET.