The Supreme Electoral Committee (SEC) announced Saturday that the newly drafted national charter was approved by 98.1 percent of voters.
SEC head Nabil Salib says 38.6 percent (20,613,677) of registered voters cast ballots in last week's referendum on the draft constitution, surpassing the 32% turnout of 2012 constitutional referendum.
The number of 'yes' voters according to Salib was 19,985,389.
More than 53,423,485 Egyptians were registered to vote in the constitution referendum that took place on 14 and 15 January, according to the SEC.
Presidential advisor for constitutional affairs Ali Saleh said shortly after the results were announced that the newly-approved charter was put in effect immediately.
The two-day vote also included clashes that led to the killing of at least nine people as security forces and supporters of the Muslim Brotherhood faced-off in several governorates.
The newly-approved constitution replaces the one drafted in 2012 by an Islamist-dominated constituent assembly.
According to the post-June 30 political roadmap, the referendum will be followed by parliamentary and presidential elections within the next six months.
Saleh said, however, the approval of Egypt's new constitution means that previous constitutional decrees by interim President Adly Mansour are void.
The 5 July decree
dissolved the Islamist-led Shura council while the 8 July decree
outlined a transitional roadmap to follow the removal of president Mohamed Morsi, which included the suspension of the 2012 Islamist drafted constitution.
"By the annulling of the 8 July decree and the implementation of a new constitution, there is now no specific road map," Saleh told Ahram Arabic news website, adding that according to article 230 of the constitution, it's up to Mansour to decide whether parliamentary or presidential elections will be held first.
He said that regardless of which elections occur first, the second elections must start within six months of the ratification of the constitution.
Another advisor, Ihab Badawy, to Mansour said the interim president had yet to decide on the timeline for elections and will address the nation on Sunday regarding the referendum.
According to Salib, 98.1 percent of Egyptians expatriates have also approved the constitution, with 15.7 percent out of a total 64,000 registered voters participating.
Around 40 percent of registered expats voted in the 2012 constitution referendum, with more than 63 percent voting in favour of the charter.
Constitutional vote in figures:
Total registered voters: 53,423,485
Turnout: 20,613,677 (38.6 percent)
Invalid votes: 246,947
Yes: 19,985,389 (98.1 percent)
No: 381,341 (1.9 percent)
Expat vote in figures:
Total registered voters: 681,346
Turnout: 107,041 (15.7)
Invalid votes: 500
Yes: 104,464 (98.1 percent)
No: 2,077 (1.9 percent)