Egypt's High Constitutional Court (HCC) on Tuesday issued a ruling suspending President Mohamed Morsi's Sunday decree reinstating the People's Assembly (parliament's lower house) – a verdict that could mark the beginning of a tense new chapter in Egypt's ongoing parliamentary saga.   

In mid-June, the HCC declared the law that governed last year's legislative polls to be unconstitutional. One day later, Egypt's then-ruling Supreme Council of the Armed Forces (SCAF) ordered the dissolution of the People's Assembly.

Morsi's executive decision on Sunday to restore parliament's lower house – one of his first acts as Egypt's first freely-elected head of state – was met with both praise and condemnation, with many legal experts questioning the move's legality. The Egyptian Judges Club, for one, an informal grouping of judicial officials, unleashed a fierce attack on Morsi and his executive decree.

The president's office, for its part, asserted that Morsi's surprise decision did not conflict with the HCC ruling that led to the dissolution of the Islamist-led People's Assembly – only with the SCAF's subsequent decision to dissolve it.

Pro-Morsi demonstrators had gathered in Cairo's Tahrir Square on Tuesday afternoon for a scheduled million-man march in support of the president's reinstatement of parliament's lower house, only to be slapped with the HCC ruling calling for the suspension of Morsi's decree.

Following the announcement of the verdict at around 7pm local time, emotions in the flashpoint square ran high.

"This decision is obviously politicised and confirms that the HCC remains a tool of the former regime," one Tahrir Square protester told Al Jazeera.

"All these judges were appointed by Mubarak," asserted another.

While mobilising in the square and the streets, the Brotherhood is also reportedly mulling legal escalation.

"We have filed a lawsuit calling for the replacement of the presiding judges, who weren't qualified to rule on the case," Muslim Brotherhood lawyer Abdel-Moneim Abdel-Maqsoud declared in the wake of Tuesday's court ruling.

Morsi and the Muslim Brotherhood, of which the new president had long been a leading member, are also demanding the abrogation of last month's SCAF-issued 'constitutional addendum,' which grants Egypt's military council wide-ranging powers at the expense of the dissolved People's Assembly and presidency.

As of press time, Morsi's office had yet to deliver a formal statement on Tuesday's constitutional court ruling.