Imam Feisal Abdul Rauf told the Al Wasat newspaper in Bahrain that the freedoms enshrined by the U.S. Constitution also reflect true Muslim values.
A portion of the interview - to be published Monday - was seen Sunday by The Associated Press.
Rauf is on a Middle East tour funded by the U.S. State Department.
He has discussed efforts to combat extremism, but has avoided any comments onover proposals for the mosque and Islamic center near the site of the toppled World Trade Center towers.
Meanwhile on Sunday, hundreds of people on both sides of the controversy rallied near the site to make their feelings known.
A crowd of demonstrators against the project stood behind police barricades three blocks from the World Trade Center site and around the corner from where the mosque and cultural center would be.
Brooklyn plumber Steve Ayling says the people who want to build the project are the same ones who "took down the twin towers."
Nearby, several hundred people who support the mosque chanted "Muslims are welcome here. We say no to racist fear."
The Sunday rallies coincided with an annual motorcycle ride by a group that raises money for Sept. 11 first responders.