President Obama has celebrated being named Time's Person of the Year 2012 by sharing cherished moments of his life.

In never-before-seen images, captured by White House photographer Pete Souza, the US leader abandons politics to give fans the father, husband and friend rarely seen in public.

The intimate snaps posted online show him bonding with his family and having fun with friends.

In one image, taken around the White House, the president pretends to be caught in an imaginary spider web while playing with one of this staffer's children, who is dressed up as Spider-man.

Another image shows Obama sharing a tender daughter-and-father moment with his eldest girl, Malia, on the swings outside the Oval Office.

"He's basically the beneficiary and the author of a kind of new America - a new demographic, a new cultural America that he is now the symbol of," Time editor Rick Stengel said as he awarded Obama the accolade.

"He won re-election despite a higher unemployment rate than anybody's had to face in 70 years. He's the first Democrat to win two consecutive terms with over 50 percent of the vote. That's something we haven't seen since Franklin Delano Roosevelt."

Obama was also chosen as Time's Person of the Year in 2008 - the year he was first elected to high office.