The US president has said the world is better and safer after the death of al-Qaeda leader Osama bin Laden.

Speaking at the White House on Monday, Barack Obama said bin Laden's death showed that the US had kept its commitment to seeing that justice was done.

Obama also praised the people gathered spontaneously at the White House and in New York to celebrate bin Laden's death, saying that embodied the true spirit and patriotism of America.

He plans to visit New York on Thursday to honour victims of the September 11, 2001 attack on the city and meet with the families of those killed.

Bin Laden claimed responsibility for planning the September 11 attacks on New York and Washington.

Bin Laden, the most-wanted fugitive on the US list, was killed in a firefight with American forces in Pakistan and quickly buried at sea.

Long believed to be hiding in the mountainous tribal region between Pakistan and Afghanistan, bin Laden was tracked down to a custom-built mansion in the town of Abbottabad, 61km north of the capital Islamabad.

Confronted by US special forces who were dropped by helicopter into the compound, bin Laden was shot dead in a 40-minute operation under the cover of night, US officials said.

Crowds gathered to celebrate outside the White House in Washington, DC, as well as in New York City - one of the sites of the September 11 attacks.