'All of us came together on 9/11 - not as Democrats or Republicans - but as Americans. In smoke-filled corridors and on the steps of the Capitol; at blood banks and at vigils - we were united as one American family,' the two senators said in a joint statement issued on Saturday.

'On Thursday, we will put aside politics and come together to renew that unity, to honour the memory of each and every American who died, and to grieve with the families and friends who lost loved ones.'

The event will mark the first time Mr McCain, the Republican nominee, and Mr Obama, the Democratic one, will appear together since they were nominated to run in the Nov 4 presidential election.

The two have rarely appeared together during the campaign.

Mr McCain had challenged Obama to a series of town hall meetings but the details could not be worked out and they were never held.

The two briefly were on the same stage at Saddleback Church in California last month but the moment lasted just long enough for a few pictures to be taken.

The two men will join on Thursday in an anniversary commemoration at Ground Zero, the site where the World Trade towers once stood.

Nearly 3,000 people died on Sept 11 in hijacked airplanes that were crashed into the World Trade Center, the Pentagon and in an Pennsylvania field.

'We will also give thanks for the firefighters, police and emergency responders who set a heroic example of selfless service, and for the men and women who serve today in defence of the freedom and security that came under attack in New York City, at the Pentagon, and in Shanksville, Pennsylvania,' the statement said. -- REUTERS