KINSHASA -- Visiting UN Secretary-General Kofi Annan on Wednesday urged respect for the sovereignty of the Democratic Republic of Congo (DRC).

Opposition party supporters shout out as they walk though the streets of Kinshasa, Democratic Republic of Congo, Wednesday, March 22, 2006. Thousands of opposition party supporters marched to U.N. peacekeeping headquarters in Congo Wednesday to demand voter registration be reopened so they can take part in landmark elections. [AP]

The DRC is a free country and "its neighbors should respect its sovereignty and refrain from certain activities," said the UN chief who was in Kinshasa on the second day of his visit to the central African nation.

He told a press conference that leaders concerned should be encouraged "to work together and try all efforts to appease the region in the interests of all countries."

Annan made the remarks after neighboring Uganda threatened to send troops into the DRC to capture the Lord's Resistance Army rebels, who are reported to operate in northern Uganda and southern Sudan, but suspected of maintaining secret camps in the northeastern part of the DRC.

On the instability of that region in the DRC, Annan said the United Nations did not accept malicious attacks on civilians and blue helmets. The Security Council has adopted resolutions against the illegal actions, he added.

Annan also expressed satisfaction over the arrest of the Congolese warlord, Thomas Lubanga, who has been held responsible for killing nine UN peacekeepers in an ambush in February 2005.

Last week, Lubanga was extradited to the International Criminal Court in The Hague to face the first trial on charges of "conscripting and enlisting children under the age of 15 years and using them to participate actively in hostilities."

Annan said the arrest of Lubanga is "a very good example...a strong message that people won't accept impunity" of criminals.