The U.N. peacekeeping chief says an escalation in fighting in Darfur has forced 138,000 people to flee their homes since mid-January and there is no political solution in sight to the 13-year conflict in Sudan's largest region.

Herve Ladsous painted a grim picture to the U.N. Security Council on Wednesday of the fighting in Darfur's Jebel Marra area between Sudanese government forces and rebels loyal to the Sudan Liberation Army's founder Abdul Wahid Elnur.

He says the security situation in other parts of Darfur remains "fragile" with persistent conflicts between local tribes over land, water and other resources.

Ladsous is urging the government and Elnur to immediately stop fighting and start peace negotiations, saying the pursuit of political objectives through military means has only contributed to prolonged civilian suffering.