New York, Sep 11 (DPA) President George W. Bush led Americans in a moment of silence Monday honouring victims of the Sep 11 attacks on the US five years ago, marking an anniversary he called "a day of renewing resolve".

The moment of remembrance at 8.46 a.m. (12.46 GMT) - the exact time a jetliner hijacked by Islamic extremists hit the first World Trade Centre tower - was the first highlight on an emotional day recalling an event that changed the US and the world.

At the gaping hole in the ground where the twin towers stood, Bush was joined by firefighters and rescue personnel involved in the response to the Sep 11, 2001 World Trade Centre attacks.

New York police officers unfurled a tattered US flag recovered from the ruins of World Trade Centre, a choir sang the US national anthem and a bell pealed to mark the precise moment.

"Five years have come and gone. And we still stand together as one," New York Mayor Michael Bloomberg told the ceremony.

Then, relatives of the nearly 3,000 people killed in the attacks began reading out the names of their loves ones, from A to Z.

Later Monday, Bush was scheduled to visit the US defence ministry building the Pentagon, struck by a third plane, as well as the site in the state of Pennsylvania where a fourth commandeered plane crashed five years ago.

To cap the day, Bush planned to address the nation Monday night in a televised speech from the White House.