Don't invite Oprah Winfrey and Natalie Portman to the same party. The rumor is that talk show queen and very pregnant Oscar winner are on the outs.

Us Weekly says Portman was supposed to be a part of Oprah's After Oscar show but cancelled just two hours before her appearance. The actress said she was "pregnant and exhausted."

However, in a behind-the-scenes episode of her talk show, Oprah appeared to be very understanding about the whole thing.

But a source tells CelebTV there was some bad blood between the two. Find out why in the video below: