Sudan's President Omar al-Bashir has unveiled a partially new cabinet, replacing two vice presidents in a move prompted by urgent calls for reform in his 24-year-old regime.

The changes, announced on Sunday, come less than a week after leading ruling party dissident Ghazi Salahuddin Atabani said he had launched a new "Reform" party relying on youth support. The party has since attracted thousands of supporters.

Atabani's departure represents the most serious split in years within Bashir's ruling National Congress Party (NCP), which has faced internal criticism over alleged corruption and stagnant leadership.

The outgoing vice presidents – Ali Osman Taha and Nafie Ali Nafie – have been veteran politicians and their departure leaves Bashir "the sole master", said Magdi El Gizouli, a fellow at the Rift Valley Institute, a non-profit organisation working in seven countries in East and Central Africa.

"It's probably the most significant reshuffle they've ever had" since 2000 when Hassan al-Turabi, a leading Islamist behind the coup, broke away and formed the opposition Popular Congress, Gizouli said…