UNITED NATIONS - Tehran on Wednesday slammed a report by a UN investigator that said human rights abuses in Iran appear to be increasing and blamed the United States and Europe for the negative assessment of Tehran.

The UN special rapporteur on human rights in Iran, Ahmed Shaheed of the Maldives, also said in his report to the UN General Assembly published earlier this week that the Iranian government had not allowed him to visit Iran while making his assessment.

Iran's Deputy UN Ambassador Eshagh al-Habib rejected the report's findings, saying the assembly's decision to appoint a special rapporteur in the first place was the "result of a one-sided approach and political ambition of certain countries in particularly the United State and its Europeans allies".

"The US as the main enemy ... of Iran spares no effort to manipulate the international community with fabricated and misleading misinformation," he said, according to the written text of his speech to the General Assembly's Third Committee, which covers human rights issues.

"This country is better off to look and correct the dark history and record of its own grave violations of human rights, not only at home, but also abroad," Habib said.

He added that Britain should "address its own humanitarian affairs related to its people who protested throughout that country to show their dissatisfaction".

Regarding Shaheed's report, Habib said that it consisted of "poorly sourced, exaggerated and outdated allegations".

"Its content is absolutely unjustified, unwarranted and unacceptable for my country," he said. "It also lacks the principles of independence, non-selectivity, impartiality."

He added that Iran had "expressed its readiness to provide all the necessary information to the Special Rapporteur (for) an impartial, balanced, nonpolitical, substantiated and well documented report". But that was not reflected in the report, he said.

Habib urged the Third Committee to "rectify and adjust" Shaheed's report.

Among the abuses by the Iranian justice system that Shaheed investigated were "torture, cruel, or degrading treatment of detainees, the imposition of the death penalty in the absence of proper judicial safeguards, (and) the status of women", according to Shaheed's report.

Shaheed also criticized the detention conditions for, and denial of rights of, Iranian opposition leaders Mirhossein Mousavi and Mehdi Karoubi and their wives, describing their situations as "deeply disturbing".