US President Barack Obama remembered the dead of the "awful" September 11 attacks in 2001, including Muslim Americans, as he marked the holy month of Ramadan at an Iftar dinner.
The president launched what will be a solemn series of events to mark the 10th anniversary of the attacks by Al-Qaeda operatives using hijacked airliners on US centers of power in New York and Washington.
"In one month, we will mark the 10th anniversary of those awful attacks that brought so much pain to our hearts," Obama told members of the diplomatic corps and prominent Muslim American community figures at the White House.
He remembered Muslim Americans who worshiped together at the World Trade Center Twin Towers in New York that were felled in an inferno and others who were part of brave emergency teams who rushed to help.
"They were taken from us much too soon. And today, they live on in the love of their families and a nation that will never forget," Obama said as he honored the victims of the attacks.
The president also honored Muslim Americans who joined the US armed services after 9/11. They fought, and sometimes died in the long decade of war in Iraq and Afghanistan.
"This year and every year, we must ask ourselves: how do we honor those patriots -- those who died and those who serve?" Obama said at the candlelit dinner in the state dining room of the White House.
"In this season of remembrance the answer is the same as it was 10 Septembers ago.
"We must be the America they lived for, the America they died for, the America they sacrificed for.
"An America that doesn't simply tolerate people of different backgrounds and beliefs, but an America where we are enriched by our diversity," he continued.
"Here in the United States there is no 'them' or 'us;' it's just us."
Obama will attend anniversary ceremonies on September 11 at all three sites where terrorists launched their deadly US attacks a decade ago, in New York, at the Pentagon outside Washington and in Shanksville, Pennsylvania, where a fourth hijacked jet was apparently brought down by its passengers.
The event in New York will coincide with the unveiling of a memorial plaza including reflecting pools on the footprints of the destroyed Twin Towers.
Iftar dinners mark the end of the daily fasting period observed by Muslims during Ramadan.