Mubarak delegated Prime
Minister Ahmed Nazif to represent Egypt at the summit in Uganda, which is expected to address the sensitive issue of sharing Nile waters, the official Al-Ahram daily reported.
In mid-July, the government press reported reported the president would be attending the summit and then on July 14 officials specifically cited the summit trip in order to discount rumors proliferating about the 82-year-old president's declining health.
"Presidency responds to rumors with an agenda packed with meetings and trips," read headline of the independent Al-Masry Al-Youm newspaper at the time, and referred to his trip to Uganda.
On Wednesday, Presidential spokesman Suleiman Awwad again dismissed reports Mubarak was ill, saying his staff were "out of breath" just trying to keep up with his schedule.
Mubarak underwent surgery in Germany in March to remove his gall bladder and a benign growth in the lining of his small intestine, setting off speculation about how long he will stay in office.
The rumors affected Egypt's stock market which witnessed sharp decline of just over 6 percent for three trading days, following the president's surgery.
Mubarak, a close U.S. ally, has ruled Egypt for three decades. He has no clear successor and has never appointed a vice president.