In a dispute that reflects the religious and political divides in this contested city, representatives of long-established Palestinian families petitioned the United Nations on Wednesday for help in trying to stop Israel and the Simon Wiesenthal Center from constructing a museum on part of a centuries-old Muslim cemetery.

It was the latest challenge to the Center for Human Dignity — Museum of Tolerance being built here by the Los Angeles-based Simon Wiesenthal Center, a Jewish human rights organization. The project has been plagued by stinging criticism and other problems since 2004, when the sponsors began digging up a 50-year-old parking lot built over part of the cemetery.

At a news conference in Jerusalem on Wednesday, Palestinian campaigners, represented by the Center for Constitutional Rights, a nonprofit organization in New York, presented their arguments for preserving the burial site, known as the Mamilla Cemetery, or in Arabic, Ma’man Allah. News conferences were also held in Geneva and Los Angeles.

In Jerusalem, Jamal Nusseibeh, son of the prominent Palestinian philosophy professor Sari Nusseibeh, said at least one of his ancestors was buried in the cemetery, which lies in what is now the predominantly Jewish western part of the city.

The cemetery, he said, is “part of the very rich fabric of Jerusalem.” The thought that anyone would want to wipe it out, he said, was “very hard to understand.”

Sixty Palestinians who say they are descendants of those buried in the cemetery have signed the petition, including Rashid Khalidi, a professor of Arab studies at Columbia University, and Abdul Qader Husseini, son of the late Faisal Husseini, a Palestinian leader in Jerusalem.

The petitioners have asked the United Nations high commissioner for human rights, the director general of Unesco and other United Nations officials to act urgently to stop the desecration of ancient graves and to declare the cemetery a protected heritage site.

Much of the cemetery has already been swallowed by development in recent decades. Israel built the parking lot over some of it in the 1960s. A school, a road and a large park now cover other parts.

Construction in Jerusalem is always accompanied by historical excavation. In the case of the museum, after ground was broken in 2004, excavators found evidence of layers of graves dating from the 11th century. A total of 250 skeletons were exhumed, and 200 more graves were exposed. The excavators estimated that the site held some 2,000 graves in all.

Responding to the latest protests, Rabbi Marvin Hier, the dean and founder of the Simon Wiesenthal Center, said in a statement: “The Museum of Tolerance project is not being built on the Mamilla Cemetery. It is being built on Jerusalem’s former municipal car park, where every day for nearly half a century, thousands of Muslims, Christians and Jews parked their cars without any protest whatsoever from the Muslim community.”

Rabbi Hier added that Israel’s Antiquities Authority had determined that there were no longer any bones or remains on the site, where infrastructure work was under way. The remains found there have been interred in a nearby Muslim cemetery, he said.

In 2008, after three years of deliberations and noting that no objections had been filed when the parking lot was originally built, the Israeli Supreme Court ruled that the museum project could go ahead. The case against it was brought by a Muslim group backed by Sheik Raed Salah, the leader of the fiery northern branch of the Islamic Movement in Israel.

Supporters of the museum said then that the fight was a political ploy by Muslim extremists trying to gain a foothold in the center of West Jerusalem. The Palestinian campaigners have argued that it is about respect for the living and the dignity and sanctity of the dead.

Adnan Husseini, the Palestinian Authority governor of Jerusalem, said he could not understand how an American institution accepted the idea of building a museum “on the bodies of others.”

The museum, according to the Simon Wiesenthal Center’s Web site, is intended to confront issues like “global anti-Semitism, extremism, hate, human dignity and responsibility, and promoting unity and respect among Jews and people of all faiths.”

Almost everything about the project has been disputed.

When the parking lot was built, for example, Israel said it got authorization from a Muslim cleric who said that a Muslim cemetery lost its sanctity if it was not in use for 37 years. The last burials in Mamilla were probably in the 1930s.

But in a letter to Gershon Baskin, an Israeli peace activist and critic of the museum project, Ahmad Natour, the president of the Shariah High Court of Appeals, Israel’s religious court for Muslim issues, stated that the sanctity of Muslim cemeteries was “eternal” and “cannot be changed until Judgment Day.” He added that the cleric in question, at the time he “authorized” the parking lot, was enmeshed in charges of criminal fraud, and that he was convicted.

The architect Frank Gehry, who drew the original designs for the museum, recently withdrew from the project after the Simon Wiesenthal Center said it needed to redesign the museum to reflect new economic realities. After a colleague was quoted as saying the project was “politically sensitive,” Mr. Gehry said publicly that his withdrawal was not for political reasons but because his staff and resources were committed to other projects.