The African Union has extended the deadline for Darfur peace talks after Sudanese rebels rejected the proposed peace deal that had been two years in the making.

"The African Union has extended the deadline of the peace talks by 48 hours as requested by the United States and other international partners to allow extensive consultations to go ahead," lead negotiator Salim Ahmed Salim said Sunday at the site of the negotiations in the Nigerian capital, Abuja.

"We are not going to sign it as it is," said rebel spokesman Hahmed Hussein earlier on Sunday. He termed it "imbalanced."

Hussein said he was speaking for both main rebel groups, The Justice and Equality Movement and the Sudan Liberation Movement, although the SLM had asked for more time.

The rebels called Sunday for changes to the deal hours before the African Union's deadline -- and after Sudan's government said it would accept the deal as is.

The three-year-old conflict has left 180,000 people dead and displaced two million people.

The rebels are seeking more influence on Sudan's government.

Wednesday's first draft of the agreement proposed the government create the role of a Darfur adviser, which the rebel groups would nominate.

It also proposed strengthening Darfur's education system by suspending school fees for five years, creating a national anti-poverty plan and asking international donors to contribute to a rehabilitation fund.

Mediators have also suggested Darfur's population vote in 2010 on whether to combine the area's three states into one geographical region. Darfur is roughly the size of Manitoba.

Nigerian President Olusegun Obasanjo pushed the rebels to sign the agreement, and met with the groups on Saturday.

"He was urging the parties to put initials on the documents," Ahmed Tugod, a leader of one JEM faction, told AP.

Rebels say Sudan's primarily Arab-dominated government has neglected Darfur, allowing it to fall into poverty and violence. The conflict started in 2003, when groups within the ethnically-diverse Darfur launched an armed resistance.

The government allegedly responded by sending the Janjaweed -- an Arab tribal militia -- to rape and murder Darfur civilians. However, Sudan denies the accusation.

As the ensuing violence escalated, a humanitarian crisis developed as thousands of Darfur refugees began seeking shelter in neighbouring Chad.

'It is too late'

Meanwhile, protesters gathered in cities across North America -- including Toronto and Vancouver -- to urge greater action by Western governments in resolving the crisis.

"Mr. Harper, you must lead/Darfur people are in need," chanted some demonstrators in Toronto.

Assaf Weisz, an organizer for the Toronto rally, said the Canadian and American governments failed to react in time to help the refugees.

"It is too late," he told CTV Newsnet. "This is an issue going on for three years now. And it's already been bubbling up."

He said the persecution of refugees is nothing short of "genocide."

The UN food agency recently said it must cut food rations to the millions of refugees because of a lack of funds.

The agency made the announcement on Friday, saying rations would be cut from 2,100 calories per person to 1,050 -- far below the suggested daily minimum.

"This is one of the hardest decisions I have ever made," World Food Program chief James Morris told AP. "Haven't the people of Darfur suffered enough?"

Jan Egeland, the UN's secretary for humanitarian affairs, said: "(Darfur) is the biggest humanitarian drama of our time."

Actor and filmmaker George Clooney, along with his father Nick, recently visited the camps in Chad housing Darfur refugees.

"If we turn our heads and look away and hope that it will disappear, it will," Clooney said. "They will, all of them, an entire generation of people."

Holocaust survivor and writer Elie Wiesel had this sad observation: "In the eyes of the victims, the world is indifferent to their plight."

Darfur activists are saying the area needs an international peacekeeping force to stabilize the region. While the Sudanese government has resisted the idea, the activists say it's time to stop asking permission.

With a report from CTV's Denelle Balfour and files from The Associated Press