(CNN) -- The State Department learned Friday that the imam behind the controversial Park51 Islamic community center project has not returned home after a State Department-sponsored tour in the Middle East.
Imam Feisal Abdul Rauf was expected to leave the United Arab Emirates on Thursday and be back in New York the same day, State Department spokesman Mark Toner said Wednesday.
However, Toner said on Friday that Rauf hadn't left the region, but had completed his mission with the department and was on his own.
This was his fourth outreach trip overseas for the State Department. In 2007, he made two similar trips to the Middle East for the Bush administration, and in January this year he traveled to Egypt, his first trip for the Obama administration.
Rauf needs about $100 million to build an Islamic community center and mosque two blocks from ground zero in Manhattan, where al Qaeda, the Islamist militant group, attacked the World Trade Center in 2001.
The project has stirred a national controversy over religious freedom and respect for the victims of the tragedy.
Opponents of the project say it would be inappropriate to erect an Islamic center and mosque so close to where the attack took place. The imam and supporters of the facility say Park51 would counter al Qaeda and promote the kind of religious tolerance such radicals abhor.
The State Department said the 15-day trip, which included rabbis, priests and other religious figures, focused on outreach to Muslim countries.
State Department spokesman Philip J. Crowley said last month that the imam would be in the region "to promote a kind of international dialogue" and had been told not to get involved in personal business, such as fundraising -- a fear many of his critics had. Crowley said he agreed to that.