A top Boston Redevelopment Authority official who previously downplayed his role in the Roxbury mosque project of the Islamic Society of Boston assisted in the city's reduction of the price the mosque backers paid for the site from $2 million to $175,000, according to BRA documents that have surfaced in lawsuits over the controversial project.

The official, Mohammad Ali-Salaam, the BRA's deputy director for planning, also raised funds for the project when he traveled to Abu Dhabi and Dubai in the United Arab Emirates as a representative of the city in 2000. The BRA board gave him permission to make the trip, which was paid for by the Islamic Society, but the BRA spokeswoman, Susan Elsbree, said yesterday that Ali-Salaam was not given permission to raise funds for the project while there.

Elsbree would not comment on the propriety of the fund-raising, but said that ''the Boston Redevelopment Authority firmly believes that Muhammad Ali-Salaam is in full compliance with conflict-of-interest law and state ethics standards as they relate to the Islamic Society of Boston's mosque development."

The documents, which were provided to the Globe, show that Ali-Salaam played an integral role at key points inside the BRA as the agency gave its approval to the Islamic Society for development of the land. They are among hundreds of pages of BRA and Islamic Society records and correspondence that are being examined by lawyers in two lawsuits...

...The records provided to the Globe show that Ali-Salaam estimated the value of the land at more than $2 million in March 2000 and later presented the BRA board with a complete development proposal that called for selling the land for $175,000.

As charges against the mosque project and its backers mounted yesterday, the Islamic Society of Boston offered to halt its legal action if opponents of the project agree to mediation of the disputes between them.

In a letter to area religious groups and lawyers for its opponents, the Islamic Society's chairman, Dr. Yousef Abou-Allaban, and his lawyer, Howard Cooper, offered to put on hold all legal action the society has brought and to go to closed-door mediation.

Cooper called the move ''a grand gesture," given what he said was the Islamic Society's strong position in the legal disputes over the mosque.

But Jeffrey S. Robbins, chief lawyer for the defendants in that suit, said the move by the Islamic Society was not a grand gesture but the result of a ''a realization that bringing their lawsuits was a very bad idea."

Robbins and Evan Slavitt, Policastro's lawyer, both said that Ali-Salaam went too far in mingling his government functions with his support for the mosque project.

In addition to the dual roles Ali-Salaam played in the BRA process and on the Middle East trip, both lawyers pointed to a letter, released by the BRA in connection with the lawsuits, that they said showed a complete blurring of his roles as official and advocate.

The letter accompanied a check for $10,000 donated to Roxbury Community College by the leaders of the Islamic Society. The letter is written on BRA stationary and signed by Ali-Salaam, Abou-Allaban, and Walid Fitaihi, a trustee for the Islamic Society.

The donation was conveyed to Grace Brown, then president of the college, with a request that Brown not reveal the source of the donation. No reason for this was given. Efforts to reach Brown and her successor, Terrence Gomes, were unsuccessful last night.

The State Ethics Commission, in letters to Ali-Salaam in 1989 and again in 2004, provided Ali-Salaam with guidelines for his advocacy of the mosque project.

The 1989 letter cautioned that his activities on behalf of the mosque ''could create the reasonable appearance of undue favoritism or conflict of loyalties," but that such impressions would be dispelled if he disclosed all relevant facts to BRA officials.

Elsbree, the spokeswoman for the BRA, said Ali-Salaam has kept his superiors at the agency fully informed.

In the October interview, Ali-Salaam told a Globe reporter that similar development deals to those with the mosque have been made with other religious groups in the past, an assertion that was supported by a staff member of the BRA public affairs department. The agency has not responded to a reporter's request to identify these comparable arrangements.

The lawsuits have chilled relations between the Islamic Society and some Jewish organizations, who say society officials have not sufficiently distanced themselves from people who made anti-Semitic statements.

Andrew Tarsy, regional director of the Anti-Defamation League, described the society's offer to stay its suit -- to put it on hold, rather than withdrawing it entirely -- as ''part of a typical litigation strategy."

''I just don' t think it's that remarkable," he said. ''Our view as an outsider is that the lawsuits have created very difficult barriers to dialogue in Boston -- and if the lawsuits were withdrawn, it would be a lot easier to get people together to have a dialogue."