Several people have been killed in fighting between rival militias in southern Somalia.
General Morgan had promised to return to peace talks
Militiamen loyal to the Jubba Valley Alliance, which controls the port of Kismayo, clashed with fighters loyal to warlord General Morgan.
A BBC correspondent says that businesses in Kismayo have closed in case the fighting spreads.
Gen Morgan is the only major warlord outside a peace process which has chosen a new Somali parliament.
The area has been tense in recent weeks, as Gen Morgan's forces have advanced on Kismayo.
He had promised to return to take part in the peace process in neighbouring Kenya, after mediators agreed to pay off the bill he had run up there in a luxury hotel before returning to Somalia.
Meanwhile, the new Somali MPs are meeting to elect a new speaker of parliament.
They are due to choose Somalia's first president in 13 years later in the month.