CAIRO, Apr 10 (Aswat Masriya) - The signing of contracts with the two international consultancy firms selected to conduct studies on the effects of the Grand Ethiopian Renaissance Dam will take place in early May, Egypt's water minister said on Friday. 

A french firm, assisted by a Dutch firm have been selected to carry out the studies on the dam's effects on water, as well as its environmental, economic and social impacts on downstream countries Egypt and Sudan. 

When Ethiopia began construction of the hydroelectric dam on the Blue Nile in 2011, concerns in Egypt surfaced regarding how the dam will affect its share of Nile water.

The water ministers of Egypt, Ethiopia and Sudan agreed on Thursday that the studies will be concluded in no longer than 11 months, Egypt's Water and Irrigation Minister Hossam Moghazi told state news agency MENA. 

Moghazi returned to Egypt in the early hours of Friday after two days of negotiations with his Ethiopian and Sudanese counterparts in Ethiopian capital Addis Ababa.

Egypt, Ethiopia and Sudan signed a declaration of principles on Ethiopian dam on March 23, during a meeting of the trio's top leadership in the Sudanese capital Khartoum.

The agreement is preliminary and negotiations between the three countries are continuing. 

Ethiopian Prime Minister Hailemariam said at the time of the signing that his country will not accept that any harm is caused to the Nile river downstream countries, "specifically, the Egyptian people."

For decades, Egypt has annually been receiving 55 billion cubic meters of the Nile river's water, the largest share, as per agreements signed in the past century.