The genocide charge follows an ICC arrest warrant issued against Bashir in March 2009 for war crimes and crimes against humanity. He has dismissed the court's claims.

"There are reasonable grounds to believe him responsible for three counts of genocide committed against the Fur, Masalit and Zaghawa ethnic groups, that include: genocide by killing, genocide by causing serious bodily or mental harm and genocide by deliberately inflicting on each target group conditions of life calculated to bring about the group's physical destruction," ICC appeals judges said in a statement.

Bashir says the allegations made by the ICC, the world's first permanent court for prosecuting war crimes, are part of a Western conspiracy. The ICC warrant was the first issued against a sitting head of state by the court.

Abdalmahmoud Abdalhaleem, Sudan's ambassador to the United Nations, called the new arrest warrant a "malignant and desperate attempt" to destabilize the country.

"We condemn this move in the strongest terms and we are confident that the Sudanese people and all peace-loving nations will ensure the demise of this criminal institution," Abdalhaleem said in a statement, referring to the ICC.

Bashir remains at large as the ICC has no police force and depends on national authorities and states that have signed up to the court to make arrests.

He has visited several countries not bound by the court's rules since the warrant was issued but the genocide charges could further restrict his movements and support from other countries, given their gravity.