The U.N. Security Council threatened new sanctions Thursday against Sudanese government officials and armed groups that attack civilians in Darfur, target peacekeepers and impede efforts to end the 12-year conflict in Sudan's vast western region.

The council made the threats in a resolution adopted unanimously that extends the mandate of the panel of experts monitoring the implementation of sanctions in Darfur until March 12, 2016. Members said they intend to review the panel's mandate and take action on further extensions by Feb. 12 of next year.

Darfur has been torn by conflict since 2003 when rebels took up arms against the government in Khartoum, accusing it of discrimination and neglect. The United Nations says 300,000 people have died in the conflict and 2.7 million have fled their homes.

Several rebel groups have signed peace deals with the government, but Darfur's two main rebel factions, the Justice and Equality Movement and the Sudan Liberation Movement, have not.

The resolution stressed that "the Darfur conflict cannot be resolved militarily and a durable solution can only be obtained through an inclusive political process."

The Security Council expressed deep concern at increased violence and insecurity in recent months and demanded that all parties halt military action, including aerial bombardments. It also demanded an immediate end to all acts of sexual violence against civilians, recruitment of child soldiers, and indiscriminate attacks on civilians, and urged the government to say what measures it has put in place to protect civilians in Darfur.

The resolution deplored Sudan's continuing violation of a requirement that it get prior authorization from the council's sanctions committee for all movements of weapons and ammunition into Darfur.

U.S. Ambassador Samantha Power accused Sudan of refusing to allow the U.N. to investigate a mass rape in the North Darfur village of Tabit last year. Human Rights Watch said in a report Wednesday that Sudanese army troops raped at least 221 women and girls in Tabit in a series of organized, house-to-house attacks.

"The horror of Tabit is just one horror, one attack of too many to count," said Power, who also accused the government of "obstruction, harassment and direct attacks that have impeded efforts to deliver humanitarian aid in Darfur.

Sudan's charge d'affaires Hassan Hamid Hassan rejected Power's accusations and called the Human Rights Watch report "fabricated."