UNITED NATIONS, Oct 21 (Reuters) - Significant human rights violations continue in Iran, though many of the country's leaders wish to move toward a more tolerant and peaceful society, a U.N. investigator said on Wednesday.

"The obstacles to be overcome in achieving this goal are very evident and success is by no means assured," said the U.N. Human Rights Commission's special representative for Iran, Maurice Copithorne of Canada.

"In short, the special representative believes that a will exists on the part of many leaders in the Islamic Republic of Iran to move the society towards a more tolerant and more peaceful condition," he wrote.

"In the meantime, significant violations of human rights continue. The government needs to broaden its agenda for change and to declare a strong commitment to achieving certain goals within specified time frames," Copithorne said.

Copithorne said the domestic reform process had been given "new life and major impetus" by President Mohammad Khatami during the period under review, from January to the end of August. But for many this process was too slow in bearing fruit and the improvements were too uncertain, while for others the process was moving too quickly and the Islamic nature of society was in jeopardy.

"The development of human rights in the Islamic Republic of Iran seems to be very much bound up with the outcome of this debate. In practical terms, the contest is impeding improvements in most of the major sectors under review by the special representative."

Copithorne, who expressed disappointment at not being invited to visit Iran, said in the area of freedom of expression, "where progress is tangible, it seems to be too often a matter of two steps forward and one step back."

In other areas, notably the legal system, there was a "promising commitment by the executive." In still others, "such as women and despite statements by the government, continuing quantifiable progress is not yet in sight."

He cited such "bright spots or potentially bright spots" as activities of the Islamic Human Rights Commission, the acknowledgment that torture exists, and reform of the prison system.

"The situation of the Baha'is has not improved," he said, referring to the country's largest religious minority who are regarded as heretics by Iran's Islamic rulers.

According to Baha'i sources not referred to in the U.N. report, the community in Iran numbers about 300,000 and more than 200 members have been executed since the 1979 Islamic revolution.

"The special representative once again urges the government of the Islamic Republic of Iran to improve its treatment of the Baha'i community," Copithorne said.

He specifically called on it to "refrain from ordering the death penalty for religious offences; to lift the ban on Baha'i organisations ... (and) to put an end to discrimination against Baha'is in all spheres of public life and services."

In a section dealing with torture or cruel, inhuman or degrading punishment, Copithorne called on the government to abolish the practice of stoning.

He also said Iranian courts had on occasion apparently sentenced persons to blinding, though the government had said such a sentence had been revoked.

According to Iranian and foreign press reports, amputation continued to be a judicially imposed punishment, chiefly for repeated theft, but the government said that, in practice, no amputations were now being carried out