KABUL, Afghanistan -- Fighting between forces loyal to two pro-government warlords in western Afghanistan Sunday left at least 12 people dead, while NATO said its forces killed 15 suspected militants who launched an attack on an alliance convoy in the south.
Meanwhile, the Afghan government and the United Nations appealed for $43 million in aid for 1.9 million people facing food shortages because of severe drought.
Hundreds of people armed with heavy machine guns, rocket-propelled grenades and small arms took part in the battle Sunday between the rival warlords' factions in the village of Waryan in western Herat province, local chief Mirwais Payman said.
The warlords Amanullah Khan and Arbab Basir are both ethnic Pashtuns who support the U.S.-backed government, Payman said.
The cause of the clash was not immediately known.
Police and Afghan army troops separated the sides, Payman said.
Also on Sunday, NATO said insurgents attacked one of its convoys in southern Zabul province with small arms and rocket-propelled grenades a day earlier, sparking a gunbattle that left 15 suspected militants dead.
Two NATO troops were wounded in the clash, the alliance said in a statement. The alliance did not disclose their nationalities.
Southern Afghanistan has seen the worst spate of violence since the 2001 U.S.-led invasion that ousted the Taliban. Thousands of people -- mostly militants -- have been killed and many more displaced as a result of fighting between insurgents and NATO and Afghan forces this year.
In the U.N. appeal for aid, officials said 200,000 more people will need food assistance than estimated in July because of extreme drought conditions. A similar appeal for $76.4 million in aid in June resulted in donations of about half that amount.
"We urge donor countries to step forward with pledges that will enable us to provide vital food and other essential living items as we approach the winter months," said Ameerah Haq, deputy head of the U.N. Assistance Mission in Afghanistan.
Afghanistan is facing a shortfall in this year's wheat harvest because of the prolonged drought, particularly in the north and northwest of the country.
Agriculture accounts for 52 percent of the impoverished nation's gross domestic product, and wheat accounts for 80 percent of cereal production.
The appeal includes planned assistance for an estimated 20,000 families displaced by fighting in the southern provinces of Uruzgan, Helmand and Kandahar, the U.N. said.