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Vice President Joe Biden joked today that his soul might be in jeopardy if he misses a scheduled reception with the U.S. Cardinals in Rome.

"We invited the American cardinals to a reception," Biden told Serbian President Tomislav Nikolic during a bilateral meeting today, according to the print pool reports. "So unless I'm prepared to join the Eastern Orthodox Church, as a Roman Catholic, I'd better show up or I'll lose my soul."

The vice president, who is the highest-ranking Roman Catholic politician in the United States, is in Rome leading the presidential delegation, which includes House Minority Leader Nancy Pelosi, D-Calif. and Gov. Susana Martinez, R-N.M., for the Inaugural Mass of Pope Francis.

The vice president and the presidential delegation will attend a reception this evening with the U.S. cardinals, members of Congress and officials from the U.S. embassies to Rome and the Holy See and the U.S. Mission to the United Nations Agencies in Rome.

Biden held additional bilateral meetings earlier today with the presidents of Poland and Italy, as well as the Italian prime minister.

While meeting with Italian President Giorgio Napolitano, Biden joked about how swiftly the cardinals selected a new pope, a feat he said would not be possible in U.S. politics.

"I didn't realize you'd arrange for a new pope so quickly," Biden joked to Napolitano.

"They are quicker than Italian politics," Napolitano replied.

"They're quicker than American politics," Biden said smiling.