Somalia's Prime Minister Omar Abdirashid Ali Sharmarke News Updates! Somalia's Prime Minister Omar Abdirashid Ali Sharmarke has resigned amid a power struggle with the country's president.
President Sheikh Sharif Ahmed's UN-backed government is battling Islamist group al-Shabab for control of Mogadishu.
Mr Sharmarke has been under intense pressure to resign for some months.
Correspondents say the squabbling has hampered the fight against the insurgents.
Islamist militants now control most of southern and central Somalia and the government runs only a few parts of the capital, Mogadishu.
Standing beside the president, Mr Sharmarke told reporters that he had decided to resign "after considering the political crisis in the government and increasing insecurity in Somalia".
President Ahmed thanked him for his "courageous decision".
The two leaders disagree over a new draft constitution.
A vote of confidence in the prime minister had been due to take place at the weekend but was postponed.
In May, Mr Sharmarke rejected as unconstitutional a vote by parliament calling for him to stand down.
