The rift at the heart of Somalia's transitional government has further widened, with the speaker of parliament saying he will relocate to Mogadishu.
Mr Adan is popular in Mogadishu
Sharif Hassan Sheikh Adan says he will leave Kenya, where the president is based, on Sunday and is trying to convince other MPs to go with him.
Mr Adan is allied to the warlords who control the capital and oppose President Abdullahi Yusuf.
Somalia has not had a functioning national government for 14 years.
President Yusuf was elected by the transitional parliament last October after two years of talks aimed at ending the warfare and anarchy.
Correspondents say Mr Adan is likely to try and set up a rival administration to that led by Mr Yusuf.
More than 80 MPs, including the warlords, are already in Mogadishu but it is not clear whether Mr Adan will succeed in gathering a quorum there - 138 members of the 275-strong parliament.
There have been reports that the rival camps are massing weapons around the town of Baidoa, which is where Mr Yusuf wants to set up his government.
Pro-president - Baidoa
President Abdullahi Yusuf
Prime Minister Ali Mohammed Ghedi
Mogadishu warlord Hussein Aideed
Anti-president - Mogadishu
Parliamentary speaker Sharif Hassan Sheikh Adan
Mogadishu warlord Mohammed Qanyare Affra
Mogadishu warlord Osman Ali Atto
Mogadishu warlord Muse Sudi Yalahow
Baidoa warlord Mohammed Habsade
He says Mogadishu is too dangerous but Baidoa is controlled by a warlord allied to Mr Adan.
On Thursday, the African Union voted to send 1,700 peacekeepers to Somalia, however, they will not go if it is not safe and the money for their deployment is not yet in place.
Prime Minister Ali Mohammed Ghedi, who is allied to President Yusuf, told the BBC that he wants the peacekeepers urgently, so the government can return to Somalia by the start of June.
He said the peace force should start by disarming the militiamen in Mogadishu but the capital's warlords are opposed to a peace force.
"Armed groups are ready to disarm but we need a third party to gather for us the weapons until we train the militias and former police," he told the BBC's Network Africa programme.
Foreign donors, who have bankrolled the long peace talks, are pressing the transitional government to relocate to Somalia.
In Washington, the United States and the European Union this week released a joint statement voicing their concern at the lack of progress.
"The Somali reconciliation process is at a critical stage. There is an urgent need for a viable agreement on relocation and security," it said.
Mogadishu warlords Mohammed Qanyare Affra, Osman Ali Atto and Muse Sudi Yalahow, who have spent years fighting each other, said that they would this week start withdrawing their forces from the capital and setting up a single militia force.
They say this will restore security in Mogadishu and remove the need for peacekeepers.
But some government officials fear that the force could be used against them, if relations continue to deteriorate.