The College of Cardinals is holding its first official meetings at the Vatican on Monday. The top agenda item is choosing which day to start the closed-door conclave that will elect the new pope. With no clear front-runner, the conclave outcome is unpredictable.
The papal resignation has put the cardinals in an unprecedented situation in modern history.
"The real mood is of shock and disappointment — this resignation desacralized the figure of the pope," says Massimo Franco, author of several books about the Vatican. He says a pope cannot be treated like a company CEO.
President Obama plans to announce three Cabinet-level nominations Monday, including a new administrator for the Environmental Protection Agency, who could be on the hot seat in the looming battle over global warming.
Gina McCarthy, currently an assistant administrator in the wing of the EPA that regulates air pollution, is the president's pick to head the EPA.