A court in the oil-rich ex-Soviet republic of Kazakhstan has granted amnesty to a prominent human rights activist.

The ruling Wednesday by the court said Yevgeny Zhovtis will be released in about two weeks under an amnesty marking the 20th anniversary of the Central Asian country's independence.

Zhovtis was sentenced to four years in prison in 2009 for manslaughter in connection with a traffic accident that killed a pedestrian.

Critics said the case was politically motivated.

The opposition has accused the government of using trumped-up charges to silence critics and opponents of President Nursultan Nazarbayev, who has been Kazakhstan's only president since it gained independence from the Soviet Union in 1991. The government denies the charge.

In a separate development, U.S. Secretary of State Hillary Clinton Wednesday announced a six-month waiver on weapons exports for Kazakhstan. Clinton said the waiver is for weapons that are defensive in nature and used to combat transnational terrorism and secure routes into and out of Afghanistan.

Kazakhstan has become an increasingly important source of oil and natural gas, and provides a key northern supply route for U.S.-led military operations in Afghanistan.