A prime challenge of the new cabinet will be to wrest control of the country from al-Shabab fighters [Reuters]

Somalia's parliament has approved the government appointed by Mohamed Abdullahi Mohamed, the country's new prime minister, after weeks of disputes, officials say.

Out of the 343 legislators who attended the parliament session on Saturday, 251 endorsed the new cabinet and 92 voted to reject it.

"The new government officially gets the approval of parliament and hence is operational," Sharif Hassan Sheikh Aden, the speaker of the house, said after the vote.

Parliament endorsed the new prime minister on October 31, more than two weeks after his appointment. But the vote to endorse the 18-member cabinet Mohamed unveiled on November 12 has been delayed by disputes.

The new prime minister is a relative newcomer to Somalia's fractious political class.

His appointment by Sharif Ahmed, the country's president, led to a bitter dispute with the parliament speaker, revealing deep rifts within the transitional administration's key players.

Mohamed's new line-up of officials sees the entry of Ahlu Sunna wal Jamaa, a powerful Sufi organisation that took up arms two years ago to fight the al-Shabab, the armed group that has been fighting the transitional government for years and controls much of the country.

The Sufi group was given the interior and labour portfolios. Ahlu Sunna is seen as a key force if the transitional government is to crush armed groups.

Only two members of the new cabinet held positions in the old line-up, which collapsed following a row between Sharif and Omar Abdirashid Sharmarke, the former prime minister.

Since its formation in Kenya in 2004, the transitional government has failed to assert its authority on much of Somalia with al-Shabab controlling 80 per cent of the country - including most of south and central Somalia and a large swath of Mogadishu, the capital.