Watch the exchange below via Reuters:
Vice President Joe Biden ended his four-day European trip in London today, where he met with U.K. Prime Minister David Cameron and Liberal Democrat leader Nick Clegg and took part in a national security meeting.
As they posed for photos at 10 Downing Street, Cameron was heard to ask Biden: "So you signed up for another four years?"
Chuckling, Biden replied, "Yes we did. It was easy, nothing to it."
The vice president said he was "delighted" to attend the British meeting, since he spends "half my life" at U.S. security meetings.
As the two men left the room, the prime minister asked after President Obama, and Biden replied, "The president is in great form."