Iraq's parliament has approved the key post of defence minister in the cabinet led by Ibrahim Jaafari.
Iraqi MPs will be relieved that a government is in place
Saadoun al-Dulaimi, a Sunni Arab, was one of six new ministers approved three months after the Iraqi election.
It is hoped that - with credible Sunnis on board - the government will be able to rob the insurgency of any support it enjoys among the disaffected minority.
Moments after the vote, however, Hashim al-Shible, a Sunni Arab, turned down the post of human rights minister.
Mr Shible told the BBC that he had not been consulted about his last-minute nomination and that he did not want to take on a post purely on the basis of his ethnicity.
His refusal was yet another embarrassment for Prime Minister Jaafari, says the BBC's Jim Muir in Baghdad.
Defence: Dr Saadoun al-Dulaimi (Sunni)
Oil: Dr Ibrahim Bahr al-Uloum (Shia)
Deputy prime minister: Abid Mutlak al-Jubouri (Sunni)
Electricity: Dr Mohsen Shlash (Shia)
Industry: Usama al-Najafi (Sunni)
Human Rights: Hashim al-Shible - refused (Sunni)
It also means further delay before he will be free to focus without distraction on the challenges facing his government.
There has been an upsurge in violence around the country since the formation of the government in late April.
At least 250 people have died.
In other developments:
- seven American soldiers are killed in a series of bomb attacks over the weekend, the US military says
- a senior civil servant from the transport ministry, Zobaa Yassin, is shot dead in his car with his driver
- US-led forces kill six and arrest 54 suspected insurgents near the Syrian border
- the Iraqi government says it has captured Amar al-Zubaydi, describing him as an aide to al-Qaeda militant Abu Musab al-Zarqawi.
The most sensitive positions filled on Sunday were the defence and oil portfolios.
Mr Dulaimi's family has its roots in the western al-Anbar province - the heartland of the anti-US insurgency led by Sunnis.
Violence has surged since the government was formed
A former officer in Saddam Hussein's army, he is a respected psychologist and statistician who has spent many years abroad and was active in the opposition to Saddam Hussein. Ibrahim Bahr al-Uloum, a Shia, fills the oil ministry portfolio.
Mr Jaafari indicated that he was seeking a woman to fill a final position in his cabinet - a deputy prime minister.
It remains unclear who will fill the position of human rights minister, following Mr Shible's refusal to take on the post.