Somalia's Transitional President Abdullahi Yusuf has arrived in the town of Jowhar, where he plans to set up a temporary base for his new government.
President Yusuf has little support in the capital Mogadishu
He was met by hundreds of people, including the prime minister, after flying in from his northern stronghold.
Earlier this month, President Yusuf told the BBC he would be bringing troops and militia with him.
Warlords from the capital Mogadishu have threatened to attack Jowhar if he establishes the government there.
"I came to Jowhar and operate from here," the president said, after meeting Prime Minister Mohamed Gedi, who has been in the town since June 18.
They set up the transitional government last year, while in exile in Kenya.
President Yusuf has been based in Bossaso in his home region of Puntland since leaving Kenya last month, in preparation for moving to Jowhar.
Somalia has not had a functioning government since the overthrow of President Siad Barre in 1991, and 13 previous attempts to end the anarchy have failed.
But the new Somali government has been divided since May.
The speaker of parliament, Sharif Hasan Shaykh Adan, is operating from Mogadishu.
But President Yusuf - who has little support in Mogadishu - has refused to move there while it is still under the control of his rivals.
The Mogadishu warlords were named as ministers in Mr Yusuf's cabinet but soon fell out with him, siding with the speaker.
Last month, President Yusuf met Mr Adan in Yemen's capital, Sanaa, but they failed to agree on where the government should be based.
Correspondents say that unless foreign powers, or Somali elders, intervene, the stage is set for a confrontation between the president and his former associates in Mogadishu.