Egypt, Ethiopia and Sudan started U.S.-monitored talks on Wednesday in the Sudanese capital to try hammer out a draft deal to resolve their dispute over a Nile dam that Ethiopia is constructing, an Egyptian spokesman said.

The $4.6 billion Grand Ethiopian Renaissance Dam project on the Blue Nile, which promises to provide much-needed electricity to Ethiopia's 100 million people, has been a contentious point among the three main Nile Basin countries.

The issue is critical for Cairo as Egypt seeks to protect its main source of freshwater for its large and growing population, also about 100 million.

The Blue Nile flows from Ethiopia into Sudan where it joins the White Nile near Khartoum, to form the Nile River. Eighty-five percent of Nile waters originate in Ethiopia from the Blue Nile, which is one of the Nile's two main tributaries, along with the White Nile.

According to Muhamed el-Sebai, a spokesman for Egypt's irrigation ministry, technical and legal teams from the three countries are to "prepare a draft deal" on how the dam's reservoir would be filled and how the dam itself would operate.

The meeting in Khartoum would last two days, he said. There was no immediate indication on whether it would succeed after several previous rounds of talks failed. But at the talks in Washington last week, the three countries said they had reached a preliminary agreement. And President Donald Trump met with the foreign ministers and those in charge of irrigation from the three countries at the White House, to push for the deal.

The U.S. and World Bank are acting as observers at the Khartoum talks after Egypt's President Abdel Fattah el-Sissi last year pleaded with Washington and the international community to mediate a solution for the years-long dispute.

Egypt claims that filling the dam's reservoir too quickly could significantly reduce its share of the Nile water, which is a lifeline for its people. A joint statement after the Washington meeting said the filling should occur in stages during the rainy season, which generally runs from July to August, thought it did not give details on how long it would take to be completed.

Another two-day meeting in Washington is planned for next week, with the goal of reaching a final agreement.

The mega-dam, now about 70% complete, will generate about 6,400 megawatts once it's finished, more than doubling Ethiopia's current production of 4,000 megawatts. Ethiopia said the dam will not be completed until 2022, more than four years behind schedule, because of faulty parts in the hydro-electrical plant's equipment.

Regional officials in Ethiopia on Tuesday confirmed 10 deaths and 250 people injured after a wooden platform collapsed during a religious event the day before.

Thousands of people attended the colorful Epiphany celebration known as Timkat in the northern city of Gondar.

"Ten people have lost their lives," the Ethiopian Press Agency quoted the city's police chief, Ayalew Teklu, as saying. "Thirteen people have sustained serious injuries, including four members of the security services."

Ashenafi Tazebew with Gondar University Hospital said more than 250 people had received medical care. Some 80 people remained at the hospital, Ashenafi said.

The collapse occurred inside the Emperor Fasilides Bath in the city where several thousand Ethiopians and tourists attended the celebration commemorating the baptism of Jesus.

The Ethiopian News Agency reported that more than 15,000 foreigners attended the event in Gondar.

UNESCO late last year added Ethiopia's Epiphany festivities to its list of Intangible Cultural Heritage of Humanity, which attracted more attendees.

Egyptian President Abdel Fattah al-Sisi said on Saturday that the cooperation with the World Bank is important for Egypt's development efforts.

Sisi's comments came during his meeting with a high-profile World Bank delegation in Cairo, spokesman of Egyptian Presidency Bassam Rady said in a statement.

Sisi said Egypt attaches great importance to its strategic relations with the World Bank Group, the spokesman added.

In addition, the meeting discussed ways to further the cooperation between Egypt and the World Bank in various fields, especially in infrastructure projects.

Officials from Egypt, Ethiopia and Sudan say they have reached a preliminary agreement aimed at clearing the way for the filling and operation of a $5 billion dam project on the Nile River.

The foreign ministers and water resources officials of the three countries concluded three days of meetings in Washington Wednesday with Treasury Secretary Steven Mnuchin and World Bank President David Malpass.

The project, called the Grand Ethiopian Renaissance Dam, is around 70% complete and promises to provide much needed electricity for Ethiopia's 70 million people. However, Egyptian officials are concerned that filing the reservoir behind the dam could significantly reduce the amount of Nile water available to Egypt.

The discussions this week were aimed at developing the rules and guidelines that would mitigate drought conditions based on the natural flow of the Nile and water release rates from the dam's reservoir.

In a joint statement, officials from the three countries said that they had agreed that the filing of the damn should be done in stages during the rainy season, which generally runs from July to August.

The guidelines said that filing the reservoir could continue into September under certain conditions with the goal of achieving the early generation of electricity while providing mitigation measures for Egypt and Sudan in case of severe droughts.

"The ministers agree that there is a shared responsibility of the three countries in managing drought and prolonged drought," the officials said in their joint statement.

The joint statement said these preliminary decisions on the damn's operation will not become final until the countries agree on all points in a final operating agreement.

The countries plan to meet again in Washington on Jan. 28-29 with the goal of reaching a final agreement on the dam's filing and operation.

"The ministers recognize the significant regional benefits that can result from concluding an agreement ... with respect to trans-boundary cooperation, regional development and economic integration," the joint statement said.

In an address to the United Nations General Assembly last fall, Egyptian President Abdel-Fattah el-Sissi said he would never allow Ethiopia to impose a "de facto situation" by filing the dam without an agreement on its operation.

Sudan said it reopened its airspace on Wednesday after an armed revolt from within its security forces shut down the capital's airport for hours and left at least two people dead.

In a press conference, Gen. Abdel-Fattah Burhan, head of the country's ruling transitional council, announced that "life has returned to normal," following a tense stand-off between the armed forces and rogue intelligence officers who had fired shots in the air to demand better severance benefits.

The burst of unrest paralyzed street life in several parts of the capital, Khartoum, along with another western city. Videos circulated on social media showing vast deployment of security forces and heavy exchanges of gunfire.

The armed forces will "not allow any coup to occur," said Burhan, adding that it's a "shame that weapons were raised in the faces of the people."

The army quickly quelled the short-lived mutiny with "minimal losses," said General Mohamed Othman al-Hussein, its chief of staff on Wednesday. Clashes killed two people and injured four others, including two officers, he added.

After trying to persuade the renegade officers to turn over their arms, the military stormed and retook the headquarters of an intelligence agency "using the least amount of force possible," al-Hussein said.

The mutiny was the latest twist in Sudan's fragile democratic transition after three decades of authoritarian rule under former President Omar al-Bashir. A sweeping protest movement ousted al-Bashir and led to the creation of a joint military-civilian government last summer.

During the transitional period, Sudan is devising ways to reorganize its armed forces. The program, al-Hussein said, requires dismantling an intelligence agency branch and merging it with a paramilitary unit known as the Rapid Support Forces, notorious for their brutal suppression of insurgencies in Sudan's restive provinces.

Unrest ensued as angry intelligence officers, who were dismissed without receiving what they considered fair compensation, took to the streets.

Sudanese Prime Minister Abdallah Hamdok described the mutiny as "discord" aimed at "cutting off the nation's transition to building a solid democracy."