The United States was represented at Friday's Vatican funeral of Pope John Paul II by President Bush, first lady Laura Bush, former Presidents Clinton and Bush, and Secretary of State Condoleezza Rice.
The White House and some close to Carter, the first U.S. president to welcome a pope to the White House when John Paul II visited in 1979, say Carter was invited.
A person in the White House told The Washington Post Chief of Staff Andrew Card, who put the delegation together, would have changed the official list if the Carter wanted to go. A Carter associate said the former president felt the final delegation was strong one.
Other Carter associates say they believe the 39th president was snubbed because of criticism Carter has leveled at Bush.
Carter national security adviser Zbigniew Brzezinski told the Post: "I think it's an outrage. It's scandalous. ... I suppose in the White House there was some resentment that (Carter) was so critical of Bush at the (Democratic National) convention."