Tripartite negotiations between Egypt, Ethiopia and Sudan over the Grand Ethiopian Renaissance Dam (GERD) are continuing on Tuesday after over a week of talks held to reach a consensus over the disputed project.

Egypt, which considers the flow of the Nile water a matter of national security, said on Monday it may resort to the United Nations Security Council to prevent Ethiopia from taking any “unilateral” action on the mega hydropower dam if Addis Ababa remains "intransigent."

Ethiopia sees the dam as key to its development, while Sudan and Egypt regard it as a threat to their water supplies from the river Nile which they share.

Following talks on Monday, Sudanese Irrigation Minister Yasser Abbas told reporters that the three countries have agreed on “95 percent” of the technical aspects related to the filling and operation of the giant dam under normal conditions and during dry periods.

The three countries “agreed on most technical aspects except for small details,” the Sudanese minister said, according to Sudan’s state news agency (SUNA).

The talks have not identified the number of the years for filling the dam’s reservoir, which would be subject to the volume of water flow, he added.

Disagreements mainly focused on legal aspects, including making the agreement binding, methods of amending it, and the mechanism to resolve disputes over the implementation of the agreement, the Sudanese minister said.

Legal teams were due to convene early on Tuesday to tackle outstanding issues before the ministers of the three countries meet.

The technical talks resumed via video conference last week in the latest bid to reach an agreement on the mega-dam, after talks stalled in February during US-sponsored meetings in Washington.

The Ethiopian irrigation ministry said the countries have “reached convergence” on issues including the rules of first stage filling, the volume of environmental flow, drought management and dam safety rules, as well as environmental and social impact assessment studies.

Ethiopia said it underlined during Monday's meeting the need to follow an approach that “ensures the joint responsibility of the three countries in the incidence of drought while preserving the optimal operation of the GERD.”

According to the Ethiopian and Sudanese ministries, the irrigation ministers of the three countries will continue the negotiations on Tuesday.

The Sudanese irrigation minister said there is no deadline for concluding the current round of talks, adding that if the countries were close to an agreement during Tuesday’s meeting, they will press ahead until they finalise the negotiations.

If the three nations fail to reach an agreement, the matter will be referred to their prime ministers, he added.

This round of meetings is being attended by representatives from South Africa, the United States and the European Union as observers.

The growing conflict has led to a diplomatic war of words between Cairo and Addis Ababa in the past months that landed at the UN Security Council.

Despite the ongoing talks since last week, Egypt and Ethiopia have exchanged blame for discord during negotiations, taking a further toll on Cairo and Addis Ababa’s relations over the dam.

Egypt said on Saturday that the revived negotiations on the GERD were "faltering," blaming Ethiopia for still displaying “intransigence” after nine years of negotiations.