"The national unity government's responsibility is to make the country's unity a choice that attracts the people," President Omar al-Bashir said in a speech at the swearing-in ceremony in Khartoum, before the Cabinet held its first session.
He urged the ministers to "redouble efforts to meet the people's aspirations and improve their living conditions".
Twenty-eight of the 30-member Cabinet were sworn in on Thursday - 15 of them from the ruling National Congress Party of President Omar al-Bashir, nine from the former southern rebel Sudan People's Liberation Movement.
The other four were from opposition movements from north and south.
The ruling party kept hold of some of the most powerful ministries, including defence, the interior - which is in charge of the police - justice and the ministry of energy and mining.
The energy post was the subject of tough wrangling between the NCP and the SPLM, since it will be a key ministry as north and south work out how to share Sudan's oil wealth.
The most notable position given to southerners was the Foreign Ministry, which went to Lam Akol, replacing Mustafa Osman Ismail of al-Bashir's National Congress. Akol split from the SPLM in the 1990s to serve as transport minister under an al-Bashir government, then returned to the rebel movement in recent years.
Al-Bashir asked the ministers to
better people's living conditions
Two ministries - science and education - were still not filled. They were given to one of the main opposition groups, the Sudanese National Democratic Alliance, which still must name who will take them.
Two women were named to ministries - Samia Mahmoud, from the NCP and Tabita Sawkaya, of the SPLA, appointed minister of welfare and social development and minister of health, respectively.
The Cabinet was due to be sworn in two weeks ago was delayed by the negotiations. Still, the government's inauguration establishes the peace process on track after a
First major step
The first major step in the process was the inauguration in July of SPLM leader John Garang in the post of First Vice President, second only to al-Bashir.
Only weeks afterward, Garang was killed on 30 July in a helicopter crash in the south, sparking angry riots by southerners and shaking hopes for peace.
But Garang's deputy in the SPLM, Salva Kiir, was quickly put in place as first vice president and as president of the new southern autonomous zone.
On Tuesday, Kiir announced that the south's legislature will hold its first session next week, another step forward.
"The national unity government's responsibility is to make the country's unity a choice that attracts the people"
The January peace accord provided for an autonomous south with its own army, national power and wealth sharing, religious freedom and a new constitution during a six-year interim period.
After those six years, the 10 southern states will hold a referendum on independence.
The government aims to incorporate Sudanese from the mostly Christian and animist south, who fought the Muslim-led government in Khartoum for 21 years, and include them in power.
The move is part of a broad attempt under the January peace agreement to give the south a share in the nation's resources - particularly oil - and a stake in the country, in part to dissuade them from voting to secede from the country in the referendum.