A number of political figures and opposition leaders have refused an invitation to attend a planned speech by President Mohamed Morsi on Wednesday.

Morsi's address comes amid mounting calls by the opposition for the president to step down in advance of upcoming mass anti-government rallies on 30 June. The street protests are predicted to be the largest since those seen during the 2011 revolution which toppled autocrat Hosni Mubarak.

In the address, Morsi will present a balance sheet of his first year in office, said presidential advisor Pakinam El-Sharkawy on Wednesday, without giving further details.

The presidency's move comes within the context of calls by Egypt's defence minister Abdel Fattah El-Sisi for political forces to reconcile. In a controversial statement on Sunday, El-Sisi insinuated that Egypt's armed forces would move in to curb mounting “friction” in the country, sparking speculations of a military return to Egypt's political scene if unrest worsens.

Some opposition figures believe Morsi's address will come too late to rein in the outpouring of outrage at his regime.

The National Salvation Front, Egypt's largest opposition coalition, said it would not attend the president's address on Wednesday, asserting it is boycotting any dialogues with the presidency.

"It's too late," said NSF spokesman Khaled Dawood. "The only way out is that the [president] accepts to hold early presidential polls."

The Constitution Party, the Free Egyptians Party and the Democratic Egyptian Party – all members of the opposition umbrella group – echoed reluctance to sit with the presidency.

The president's opponents argue that even compromises such as a government reshuffle or amendments to the constitution would not contain mounting discontent among large swathes of the public.

The Egyptian presidency has, however, denied that there any plans for an imminent cabinet reshuffle and reiterated that Egypt's military was not at odds with the presidency, despite recent speculation to the contrary.

The replacement of Egypt's current cabinet with a government of “national unity” has been a longstanding demand of Egypt's opposition in light of perceived failures of the Islamist-led regime to handle Egypt's transition to democracy.

"It's illogical that the opposition sits with the presidency to listen to flimsy excuses and flimsy achievements while the country is falling apart," read a statement published by the Free Egyptians Party on Wednesday.

President Morsi's Islamist backers meanwhile are planning to stage an open-ended sit-in on 28 June, to counter upcoming anti-regime protests and "support the legitimacy of the president."