The U.N. says Rwanda is threatening to attack Hutu rebels based in the neighboring Democratic Republic of Congo. Meanwhile, Kigali says the rebels are advancing toward Rwanda's border. There have not yet been any clashes, but there is concern that fighting could soon erupt in the region. 

No sooner had the United Nations Security Council left the Democratic Republic of Congo, where it had spent several days trying to consolidate a fragile peace, Rwanda told the U.N. late on Tuesday it was ready to launch attacks on Rwandan rebels in Congo.

A U.N. spokeswoman said Wednesday that a senior Rwandan official telephoned the head of the U.N. mission, William Swing, threatening an attack on the Rwandan Hutu rebels that have roamed in eastern Congo for the last decade. Meanwhile, Rwanda said Wednesday that the Hutu rebels, known as the FDLR, were already advancing toward the Rwandan border with the intention of attacking, and Kigali warned it would do whatever it took to protect its borders.

Many of the extremist Hutus that took part in Rwanda's genocide in 1994, killing 800,000 Tutsis and moderate Hutus, fled to eastern Congo after they were defeated. Over the last decade they have launched sporadic attacks on Rwanda. For its part, the government in Kigali has invaded Congo twice during the last eight years, ostensibly to defeat the Hutu rebels.

Critics have accused the government of trying to maintain political and economic influence in eastern Congo. Some of the Rwandan combatants have returned home through a U.N.-run disarmament and repatriation program, but some 10,000 are thought to still remain in Congo. Their political leaders have demanded dialogue with the government in Rwanda. But Kigali has refused and, in turn, accused the U.N. of failing to deal with the rebels.

Patricia Tome, the U.N. spokeswoman in Congo, said that the U.N. would not accept the Rwandan threat and the international community would react firmly. Meanwhile, a spokeswoman for the mission in the east of the country said that there were no signs of the Rwandan rebels advancing toward the border.

A Congolese government spokesman labeled as unacceptable the Rwandan threats, which come less than a week after regional leaders signed up to work together toward peace and development. The spokesman said that Rwanda should not destroy the process that the presidents of the two countries had been working on. Analysts fear that the latest crisis could plunge Congo back into war, just as the vast African nation is trying to recover from a five year conflict that sucked in six neighboring countries and killed about three million people.