Sisi took to Twitter soon after the results were announced to thank his fellow citizens “who dazzled the world with their awareness of the challenges facing” Egypt.

Around 27 million votes were cast in the Arab world’s most populous country, with a turnout rate of 44.33 per cent.

Rights groups have criticised the conditions surrounding the rushed vote, including the suppression of those opposing the sweeping changes that consolidate Sisi’s power.

Egypt’s parliament, stacked with Sisi loyalists, voted in favour of the amendments last week, giving voters just days to digest the changes to 20 articles.

Other controversial amendments include boosting Sisi’s control over the judiciary and giving the military even greater influence in Egyptian political life.

Sisi has argued he needs longer to complete the job of restoring security and stability after the turmoil that followed the overthrow of veteran autocrat Hosni Mubarak in the Arab spring of 2011.

A vote in Sisi’s favour was expected but analysts worried about its consequences.

Voters offered free rides and food to encourage them to vote in Egypt’s referendum on President Abdel-Fattah el-Sissi’s term in power

Analyst Mai El-Sadany, legal director at the Washington-based Tahrir Institute for Middle East Policy (TIMEP), said the amendments could have “long-term negative implications for Egypt”.

The main amendment, which has set the nation abuzz, is the near certainty that Sisi will run for another six years in office when his term ends in 2024.

His current term was to end in 2022 but was retroactively updated with an extra two years.

“What is coming is extremely bad … it gives the message that I am your God and no one will come near the throne as long as I’m in power,” said veteran Cairo University political scientist Hassan Nafaa.

“How can a constitution be changed to tailor-fit one person?” he asked.

Domestically and internationally, Sisi has presented himself as a bulwark against terrorism and a rock of political stability amid a region in turmoil.

“These constitutional amendments empower the executive and military at the expense of a weakened judiciary and legislature” said Sadany of TIMEP.

“Doing so eats away at the separation of powers, it deteriorates the rule of law, and it silences spaces for independent dissent.”

Under Sisi, authorities have silenced all forms of political opposition in a sweeping crackdown on Islamists as well as secular and liberal activists.

Rights groups have consistently criticised these heavy-handed tactics.

Human Rights Watch’s deputy director for the Middle East and North Africa, Michael Page, called the amendments “a shameless attempt to entrench the military’s power over civilian rule” and said the referendum “took place in such an unfree and unfair environment that its results can have no pretence to legitimacy”.

Mustapha Kamel al-Sayyid, a professor of political science at the American University of Cairo, said the amendments set a dangerous precedent for future rulers beyond the tenure of 64-year-old Sisi.

“This (raft of amendments) is unprecedented in the (modern) history of Egypt,” he said.

The constitutional package strengthens “the hand of one individual over everyone else … it will be very difficult to go back on because who will give up so much power?” Sayyid added.