Ethiopia has maintained that it had evidence about Egypt's support to rebels against the Addis government in order to secure the River Nile waters.
Egypt has denied the accusation.
Ethiopian Prime Minister was early this week quoted by Reuters news agency as saying that Egypt could not win a war with Ethiopia, hence Cairo's strategy to support rebel groups to destabilise the neighbouring state.
Mr Meles termed the alleged move unfortunate as there were efforts to ensure equitable sharing of the Nile waters.
Ethiopian Government spokesman Shimeles Kemal told the Africa Review that Addis had concrete evidence on Egyptian covert support to armed rebel groups.
We will give the details at the right time, Mr Shimeles said.
Intelligence sources within the Ethiopian Government also hinted that Addis was preparing to make public its evidence against Egypt.
The sources claimed that Ethiopia's arch-foe Eritrea, was helping Egypt to reach the rebel groups.