Mahjoub Fadul, a presidential spokesman, said: "The president issued a decree to reshuffle the cabinet and the reshuffle included two presidential advisors, six ministerial posts and six ministers of state in the national government."
Among those affected by the reshuffle is Lam Akol, the former SPLM foreign minister, who will become the minister of cabinet affairs.
There had been speculation that Akol had displeased the SPLM by too often following the line of their former foes, al-Bashir's National Congress Party (NCP).
Observers said Akol's removal from the foreign ministry was key to the reshuffle.
Under the 2005 peace deal, the SPLM takes about a quarter of cabinet posts, which also shared oil revenues, outlined democratic transformation and enshrined elections and a southern vote on secession by 2011.
Riek Machar, the SPLM vice chairman, said on Tuesday that the party wanted progress on key elements not yet implemented in the 2005 deal.
He said these included demarcating the north-south border, the status of the oil-rich Abyei region and the redeployment of northern troops from the oil fields by January 9, the agreement's third anniversary.
The SPLM also filed complaints about political prisoners, constitutional violations and the NCP using their mechanical majority to push through legislation.