Downey Jr first donned the character in 2008 when he filmed "Iron Man".
The news was announced by Marvel Studios bosses but there was notably no mention of an "Iron Man 4", reports femalefirst.co.uk.
"The Avengers 2" is expected to hit theatres in 2015 and will see Downey Jr reteam with Mark Ruffalo as Hulk, Chris Hemsworth as Thor and Chris Evans as Captain America.
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