Amnesty International says that weapons from Russia and China are being used by the Sudanese government to commit serious human rights violations against civilians.
The international rights group said in a report that Moscow and Beijing continue to supply weapons and munitions to Khartoum, despite "compelling evidence" they are being used against civilians in Darfur.
The organization said Russia and China have provided Sudan with significant quantities of ammunition, helicopter gunships, attack aircraft, air-to-ground rockets and armored vehicles.
Amnesty is calling for the United Nations to suspend all international arms transfers to Sudan and extend an arms embargo to the entire country. Currently, governments must receive guarantees that the imported arms will not be used to commit atrocities.
The Sudanese government has been fighting rebels in the western Darfur region since they began an anti-government campaign in 2003. The United Nations says more than 300,000 people have been killed in the conflict. It estimated last month that 1.9 million people remain displaced.
The International Criminal Court has indicted President Omar al-Bashir for alleged war crimes and genocide in Darfur. The court accuses him of masterminding a campaign of murder, rape, and other atrocities against civilians in the region.
Some information for this report was provided by Reuters.