Sudanese President Omar al-Bashir has returned to Khartoum from South Africa, avoiding arrest over war crimes charges on an international warrant, BBC News reports.

Bashir flew out of South Africa despite an order barring him from leaving while a Pretoria court decided whether to arrest him on charges issued by the International Criminal Court.

Bashir was visiting Johannesburg for an African Union (AU) summit.

An ICC official said the failure to arrest Bashir was "disappointing". "We still remain quietly optimistic and determined to see justice done in this case," deputy prosecutor James Stewart told the BBC.

The Pretoria High Court issued an order for Bashir's arrest hours after his aircraft left the country.

A South African judge, Dunstan Mlambo, meanwhile said the failure to arrest Bashir had violated the country's constitution.

However, Sudan described the attempt to arrest Bashir as "lame and meaningless". Foreign Minister Ibrahim Ghandour told reporters at Khartoum airport that the court order was an attack on Sudanese sovereignty.

Bashir arrived at the airport on Monday, June 15 evening, dressed in white robes and waving a cane. He was greeted by cheering supporters.

The Sudanese leader is accused of committing war crimes, crimes against humanity and genocide during the Darfur conflict.