Egypt’s foreign minister Sameh Shoukry said, Technical talks between Egypt, Sudan and Ethiopia over Ethiopian dam failed to make a breakthrough on Monday.

Egypt and Ethiopia are at the construction of the grand renaissance dam, a $4 billion-hydroelectric project that Cairo fears will reduce waters that run to its fields and reservoirs from Ethiopia’s highlands and via Sudan.

Addis Ababa hopes the dam will make it a hub for the electricity-hungry region and denies it will undermine Egypt’s access to water.

Egypt’s foreign minister Sameh Shoukry said technical experts who met in Addis Ababa last week did not achieve a breakthrough.

Shoukry told during a news conference in Cairo with Ugandan counterpart, I have spoken to the minister of irrigation, who attended this meeting, and what has reached me is that the obstruction that has bogged down this path for more than a year has not been overcome.

Ties between Egypt and Sudan were strained when Khartoum backed the dam because of its need for electricity.

The three African neighbors are set to meet on May 15 for further talks, Shoukry said, adding Egypt had initially proposed several earlier dates for negotiations, but they were turned down by the two other countries.

Earlier this month, talks in Khartoum between Egypt, Ethiopia and Sudan also failed to reach agreement, but were described by Sudan’s foreign minister as constructive.