"In Zimbabwe, civil society remains under siege amid a political and economic crisis caused by the irresponsible policies of the regime," Rice said at an award ceremony to mark International Human Rights Day.

Rice gave the State Department's annual Freedom Defender Award to the Zimbabwe Lawyers for Human Rights, a nongovernmental organization that has given legal help to activists who oppose President Robert Mugabe.

"Over the past several months, the authorities have engaged in an intensified campaign of repression, characterized by harassment, intimidation, arrests and violent assaults against peaceful opposition activists, professionals, independent labor leaders and other members of civil society," Rice said.

She said the lawyers' group, represented at the ceremony by its president Arnold Tsunga, had taken on the dangerous task of defending those persecuted by Mugabe's government.

"We thank you and your colleagues for your courage," Rice told Tsunga as she handed him the award, which is symbolic and has no monetary value.

The United States says this year is the worst on record for human rights in Zimbabwe, with about 6,000 instances of abuse and over 90 politically motivated kidnappings and abductions.

Last week, the United States imposed travel and financial sanctions on about 40 more people with ties to Mugabe, who has been in power since independence from Britain in 1980.