CAIRO -- Egypt's first legislature in more than three years, a 596-seat chamber packed with supporters of President Abdel-Fattah el-Sissi, held its inaugural session on Sunday, signalling the completion of a political road map announced after the 2013 military overthrow of an elected Islamist president.

The assembly, elected in November and December, is the first legislature since el-Sissi, as military chief, led the 2013 ouster of President Mohammed Morsi following mass protests against the Islamist leader and his Muslim Brotherhood. The new parliament replaces one dominated by Islamists that was dissolved by a court ruling in June 2012.

The new chamber's first task will be to ratify some 300 presidential decrees issued by el-Sissi since taking office in June 2014 and Interim President Adly Mansour before him. Under the constitution, these decrees must be ratified within 15 days starting from the date of the inaugural session. Failure to do so will result in the automatic repeal of the laws.

The decrees include a law severely restricting street demonstrations and a terror law that curbs press freedoms and gives police sweeping powers.

Sunday's session was supposed to be a mostly procedural one, with lawmakers taking the oath and electing a speaker and two deputies. But heated arguments between lawmakers broke out when an outspoken member, Murtada Mansour, strayed from the text of the oath to avoid endorsing the Jan. 25, 2011 uprising against autocrat Hosni Mubarak.

Mansour, an el-Sissi supporter and president of one of Egypt's top soccer clubs, changed the part of the oath where lawmakers pledge respect for the constitution, saying instead he will respect the "clauses of the constitution," thus avoiding implicit support for the charter's prologue. That part of the document contains praise for both the 2011 revolt as well as the so-called "June 30 revolution," a reference to the wave of massive street demonstrations that led to Morsi's ouster on July 3, 2013.

The dispute reflects an ongoing and divisive argument in Egypt regarding the legitimacy and legacy of the original 2011 uprising. Many pro-el-Sissi politicians and media figures, like Mansour, now brand the 2011 revolt as a mistake -- fueled and funded by external powers and foreign agents seeking to weaken Egypt. Other el-Sissi supporters regard both Mubarak's and Morsi's ousters as legitimate revolutions. Few in the public sphere are willing to criticize the "June 30 revolution" that eventually brought el-Sissi to power.

"I don't recognize January 25, that is my prerogative," a visibly angry Mansour said over the shouts of other lawmakers.

Interim speaker Bahaa Abu Shaqah demanded that Mansour read the official text of the oath, but he refused. Abu Shaqah left his seat, threatening to adjourn the session, but changed his mind when Mansour, who is notorious for his frequent outbursts of abusive language when on the air, relented.

"I will read it, but it is the first oath that I took which comes from the heart," he said, when he finally relented and read the official text. Mansour, however, sparked another row when he hurriedly and casually read the oath.

Sunday's oath controversy harkened back to the inaugural session of the 2012 legislature, when ultraconservative Salafi lawmakers insisted on adding to the end of the oath the phrase "as long as it does not clash with God's law."

After Morsi's overthrow, El-Sissi announced three steps to take Egypt back to democratic rule: The adoption of a new constitution and presidential and parliamentary elections.

But the process has unfolded against the backdrop of a harsh crackdown on Islamists and secular and the leftist pro-democracy activists who fueled the 2011 uprising. Thousands have been jailed and hundreds of Islamists killed in a series of clashes with security forces in 2013 and 2014. The Muslim Brotherhood, which swept every election following Mubarak's ouster, is officially branded a terrorist group.

Turnout for last year's parliamentary elections was around 30 per cent, and most of those elected to the assembly support the president.

On Sunday, el-Sissi vowed to support the chamber and respect the separation of powers, according to a statement issued by his office. Under the constitution adopted in 2014, perhaps Egypt's most liberal, the legislature has the right to impeach the president and sack the prime minister, albeit under strict conditions.

A pro-el-Sissi coalition in parliament, called "Supporting Egypt," enjoys the support of 366 lawmakers, according to its leader, retired army general Sameh Seif el-Yazl. It is designed to ensure continued support for the president and thwart any attempt to hinder his policies.

Law professor Ali Abdel-Al of the "Supporting Egypt" coalition was elected speaker of the legislature, winning 401 votes, nearly 10 hours into the marathon session.

"I hope this legislature brings about the democracy that people have hoped for," Abu Shaqah, the interim speaker, said in parting comments before giving up the speaker's seat to Abel-Al.

Addressing the assembly, Abdel-Al thanked el-Sissi, whom he described, to a standing ovation and applause, as the "leader president" and "leader of the march" -- lofty titles typically associated in the Arab world with authoritarian leaders. "I will always be defending democracy and the national principles of the January 25 and June 30 revolutions," Abdel-Al said.

El-Sissi, who is expected to address the chamber later this month, has since his election in 2014 been focused on restoring security and reviving the nation's ailing economy.

Egypt is grappling with an increasingly potent Islamist insurgency centred in the northern part of the Sinai Peninsula, which claimed the downing of a Russian passenger plane over Sinai in October that killed all 224 people on board and led to widespread flight cancellations, dealing a major blow to the vital tourism industry.

Egypt's economy has been kept afloat by billions of dollars from its oil-rich Gulf Arab backers injected into its emptying coffers. Still, the local currency, the pound, has been under growing pressure, tourism battered from years of turmoil and double-digit inflation, currently running at nearly 11 per cent.