Mahmoud al-Zahar said Muslims "have to build everywhere" so that followers can pray, just like Christians and Jews build their places of worship.
Al-Zahar spoke Sunday on "Aaron Klein Investigative Radio" on WABC-AM. He is a co-founder of Hamas and its chief on the Gaza Strip.
Sen. Chuck Schumer says al-Zahar's comments don't carry any weight because Hamas is a terrorist organization. Schumer hasn't taken a stand on the mosque.
Rep. Peter King, who opposes the mosque, says he won't respond to Hamas.
The mosque is a project of the Cordoba Initiative, an advocacy group that promotes improved relations between Islam and the West. It didn't respond to al-Zahar's comments.
White House: Politics had no role in remarks
A White House spokesman said Sunday that politics was not a factor in President Barack Obama's remarks about building a mosque near the site of the September 11, 2001, attacks in New York City.
Deputy press secretary Bill Burton said it was "not politics" but Obama's feeling that he had the obligation as president to "make sure people are treated equally" under the US Constitution.
Obama has said that religious freedom allows the mosque to be built, but without commenting on the wisdom of building one two blocks from an area known as ground zero. Republicans have pounded him for his comments, making it a November election issue.
Burton said Obama "felt it was his obligation as president to address this." Obama was on a political trip to the state of Wisconsin.
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