Branding the poll a "charade", the coalition of eight parties and 150 public figures yesterday announced a campaign under the slogan "Stay at home" ahead of voting on March 26- 28.
"No to participation in this charade," said Hamdeen Sabbahi, a presidential candidate in 2012 and 2014.
At a news conference by the coalition, founded in December and describing itself as a democratic civic movement, Sabbahi asked: "How can we speak of an election when there is no guarantee of a free vote?"
Before becoming president in 2013, Sisi led the military in ousting the North African country's first freely elected leader, the Islamist Mohamed Morsi.
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The next year Sisi stormed to victory in the presidential election after security forces crushed all his Islamist and liberal opponents and sent hundreds of them to prison.
Sisi silenced all forms of political opposition during his first four-year term.
Ahead of the March election, all potential presidential contenders have either been hobbled or have thrown in the towel, claiming the entire process was rigged.
Egypt's National Election Authority announced last evening that it has validated the candidacy of Sisi and Mussa after they "met the legal requirements".