The United States on Tuesday pressured Sudan (search) to quell bloodshed plaguing the African country's western region, with the State Department's second-in-command proclaiming "the eyes of the world are on Darfur."

"The world knows what is happening in Darfur and the government cannot escape the consequences of that knowledge," Robert Zoellick, top deputy of Secretary of State Condoleezza Rice, told donors at an international conference for Sudan.

He called on the Khartoum-based government to stop Arab militias and hold people accountable for atrocities as well as assist the African Union (search) to monitor military flights over the bloodied swath of Sudan.

After pledging more than $1.7 billion, mostly for humanitarian aid and reconstruction assistance in the devastated southern region, Zoellick put a condition on future financial aid. "For us to sustain support, particularly related to the government in Khartoum, we're going to have to see action in Darfur," he said.

For its part, Zoellick said the Sudan People's Liberation Movement (search) must work with Darfur (search) rebels to comply with a cease-fire.

An estimated 180,000 people have died and more than 2 million have lost their homes since early 2003 when black African farmers clashed with government-backed Arab militias in what former Secretary of State Colin Powell has called genocide.

"The violence and atrocities in Darfur cast a dangerous shadow over our work," Zoellick told other donor countries here. "We need to see an end to atrocities and the return of peace in Darfur."

The North and South, Zoellick said, can't be committed to achieving peace in accordance with their January agreement to end a two-decade old civil war without addressing violence in the western region. Failure would mean "Sudan could slip back into the depths," he said.

Zoellick, who is visiting Darfur later this week, met with leaders of the mostly Arab Sudanese government in the North and the black African rebels who control the South while in Norway. He said both sides indicated they don't want continuing strife in Darfur.

Still, in a statement, the Sudan People's Liberation Movement group — the said implementing the peace agreement would provide "the best opportunity for the resolution of the conflicts in Darfur and Eastern Sudan."