The big question at Columbia University this week is whether the tensions between President Lee Bollinger and the dean of the School of International and Public Affairs, Lisa Anderson, led Ms. Anderson to step down.

The press office at the university confirmed yesterday that the dean, who has come under criticism for siding with anti-Israel factions on campus and for taking a junket to Saudi Arabia paid for by the regime in Riyadh, is leaving the post she has held for 10 years. Professors at SIPA said Ms. Anderson circulated an e-mail message at the end of the summer announcing her resignation, effective at the end of the academic year. It cited her desire to get back to teaching and research.

However, speculation is spreading on campus as to whether Ms. Anderson is stepping down because of tensions with Mr. Bollinger in the wake of his abrupt decision to overrule Ms. Anderson’s plan to welcome the Iranian president to the World Leaders Forum on campus. Ms. Anderson’s offer of hospitality to a leader who has called for Israel to be wiped off the map and who has denied the Holocaust drew criticism on campus from professors and students alike.

“I think the president asked her to resign,” a political science and SIPA professor at the university, Rudolpho de la Garza, said. He said tensions are inherent between high-level university officers, adding: “It’s hard to have tensions with a university president because if you’re in trouble he can wipe you out.” Mr. de la Garza said he had witnessed only “good tension” between the two, but that the importance of SIPA to both Ms. Anderson and Mr. Bollinger could put them at odds. Mr. Bollinger’s office did not return phone calls seeking comment.

Ms. Anderson, a former president of the Middle East Studies association, attracted criticism for her decision to invite Libya’s strongman, Muammar Gadhafi, to the university in March. Colonel Gadhafi took the opportunity to deliver a lecture on democracy, proclaiming Libya the only democracy “on the whole planet.”

Ms. Anderson sat on the committee convened by Mr. Bollinger in 2005 to investigate students’ charges that professors in Columbia’s Middle East studies department silenced dissent in their classrooms. She signed a letter addressed to Mr. Bollinger that equated the students’ grievances to a “campaign of defamation.”

Mr. de la Garza said Columbia’s provost and vice president are in the process of gathering a committee to choose Ms. Anderson’s successor. Columbia’s provost, Alan Brinkley, is out of the country and could not be reached for comment. A SIPA professor who asked not to be identified said that considering the importance of SIPA to the university, the committee will look to appoint somebody with a very high profile.

Ms. Anderson’s future plans are unclear. Professors who work closely with her have speculated that she may return to her chair at Columbia and resume teaching, take time off, or look to become president of a small college.