The International Committee of the Red Cross and Red Crescent said more than 3,000 people have been displaced by tribal clashes in the Nafusa Mountains, about 100 miles south of Tripoli.
"Some of the displaced are living in difficult conditions, as they have taken shelter in unfinished buildings," the ICRC aid distributor Asma Khalik Awan said in a statement.
U.N. special envoy to Libya Tarek Mitri condemned political violence that this week targeted the convoy of President of the General National Congress Mohammed Magariaf, whose convoy came under fire this week.
All Libyans are called on "to refrain from settling political issues through violence and to resort to peaceful means in expressing their demands," Mitro said in a statement.
The GNC is working to develop the framework for an eventual election for the Libyan Constituent Assembly.
Libya is trying to secure political developments in the wake of civil war. Long-time leader Moammar Gadhafi died after falling into rebel hands following a NATO-led intervention in 2011.