What Obama promised Biden

(CNN) - Before he accepted Barack Obama's offer to join his presidential ticket, Joe Biden got a promise from Obama: that he would be there for "every critical decision," Biden said in an interview broadcast Sunday.

Speaking to ABC's "This Week," Biden said he believes the vice president's role is to provide "the best, sagest, most accurate, most insightful advice and recommendations he or she can make to a president to help them make some of the very, very important decisions that have to be made."

When Obama talked to him about being his number two, "I said, 'I don't want to be picked unless you're picking me for my judgment. I don't want to be the guy that goes out and has a specific assignment... I want a commitment from you that in every important decision you'll make, every critical decision, economic and political, as well as foreign policy, I'll get to be in the room.'"