|The White House said Obama's trip will recall the unity that existed in the aftermath of the deadly attacks [AFP]
The US president has arrived in New York, where he will visit Ground Zero to meet families of people killed in the September 11, 2001 attacks on the US.
The attacks are believed to have been ordered by Osama bin Laden, the leader of al-Qaeda, who was killed by US forces earlier this week.
The president first paid a visit to Engine 54, a fire station from where 15 firefighters died attempting to save the nearly 3,000 people who were killed after planes were flown into the World Trade Centre.
Later, Obama will lay a wreath at Ground Zero, his first visit to the area since he became president.
The White House has stressed that Obama's visit was a not a victory tour following bin Laden's killing, but a form of homage to the victims of the attacks that triggered Washington's "war on terror" against al-Qaeda nearly a decade ago.
Obama invited George Bush, his predecessor who was president at the time of the attacks, to join him at Ground Zero. However, Bush declinedthe invite.
"This is a moment of unity for Americans and a moment to recall the unity that existed in this country in the wake of the attacks on 9/11," Jay Carney, the White House spokesman, said. "The invitation was made in that spirit."
Obama ratings surge
Carney described the death of bin Laden as a "cathartic moment for the American people", adding that Obama wanted to "honour the spirit of unity in America that we all felt in the wake of that terrible attack".
"He wants to meet with them and share with them this important and significant moment, a bitter-sweet moment, I think, for many families of the victims," he said.
The killing of bin Laden during a helicopter-borne commando raid deep inside Abbottabad is undoubtedly one of Obama's chief political triumphs since taking office in 2008, analysts said.
Polls showed an immediate surge in his ratings and even the usually squabbling Washington political establishment has rallied around the president.
There will be no public speech during the Ground Zero visit and the meeting with families will be private.
The reticence has been portrayed as part of the same attempt to retain an atmosphere of dignity in the wake of bin Laden's killing.
Obama has personally ordered that photographs of the al-Qaeda leader's dead body remain secret - despite a clamour from many people for some visual proof of his demise.
The Reuters news agency released several pictures of people killed in the operation that it said were taken by a Pakistani security official about an hour after the assault.
In an interview with 60 Minutes, the CBS news programme, Obama said: "It is important for us to make sure that very graphic photos of somebody who was shot in the head are not floating around as an incitement to additional violence.
"As a propaganda tool. You know, that's not who we are. We don't trot out this stuff as trophies.
"The fact of the matter is this was somebody who was deserving of the justice that he received.
"And I think Americans and people around the world are glad that he's gone. But we don't need to spike the football."