An estimated 54 million Egyptians, of a population of around 85 million, have the right to vote in the forthcoming constitutional referendum, an official has said.
A referendum on the newly-amended charter, which replaces the one suspended by the interim government following the ouster of Islamist president Mohamed Morsi in July, is slated for 14 and 15 January.
Around 53 million Egyptians are eligible to vote in Egypt, in addition to some 682,000 expatriates, head of the state Higher Elections Committee Tarek Saad said on Monday.
The number of eligible voters in the upcoming poll is higher than the nearly 52 million who were eligible to vote on the 2012 Islamist-drafted charter signed into law by Morsi during his year in office, according to Saad. A turnout of almost 33 percent was reported at the time.
The referendum – the first watershed in a transition roadmap – will be followed by parliamentary and presidential elections by mid-2014, interim authorities said.
The supporters of deposed president Morsi announced they would boycott the poll after having initially contemplated calling for a 'No' vote, a spokesman for the Muslim Brotherhood-led National Alliance to Support Legitimacy said on Monday.
The Islamist coalition had declared the rewriting of the charter illegal and expected the vote would be rigged, but stopped short of announcing a boycott.
A spokesman for the alliance, Hamza El-Farawy, told AFP on Monday that his group "reject[s] any vote under military rule."
Farawy added that the Islamist coalition, which has been calling near daily protests against interim rulers, would launch a boycott campaign.
Islamists won all successive elections after the fall of autocratic president Hosni Mubarak in 2011, with the Brotherhood's Morsi becoming Egypt's first democratically elected president in 2012.
Morsi was ousted by Egypt's army in July following mass nationwide protests against his turbulent one-year rule, with critics accusing him of economic mismanagement and consolidating power in the hands of the Brotherhood.