Somaliland's government declared autonomy from Somalia in 1991, but has not gained widespread international recognition for independence.
"Any dialogue that transpires between Somaliland and Somalia will not discuss unification, but rather how the two previously united countries can move forward separately," Somaliland's government said in a statement late on Sunday.
Somaliland, which has remained largely peaceful for over three decades while its neighbour has been convulsed by civil war, said it "has no plans for dialogue to discuss unity with Somalia."
Some clan elders in disputed areas along Somaliland's border with Somalia's semi-autonomous Puntland state say they want to be part of Puntland rather than Somaliland.
FILE - Workers offload goods from a docked ship at the seaport of Berbera in Somaliland, a breakaway region of Somalia, on Feb. 10, 2022.
Heavy fighting broke out between Somaliland forces and militiamen in and around the town of Las Anod in one such area in February.
Museveni's statement came a day after meeting Jama Musse Jama, a special envoy for Somaliland, in which he said "Somalia and Somaliland should do away with politics of identity if they want prosperity for their country."
Museveni's deputy press secretary said Uganda's state house had no comment on Somaliland's statement.
Somalia's information and interior ministers did not immediately respond to requests for comment, though Somalia's position has consistently been that it considers Somaliland part of Somalia and wants unification.