"I believe we will have to have something new and not return to what it was like before 2014," said al-Nujaifi, also head of the country's Muttahidoon political coalition, one of the largest Sunni blocks in the country.
"A situation that will give everyone a chance to participate in and have a say in governance of economy and security but under the umbrella of one Iraq and one constitution … Our only option is to regionalize the provinces … a federal Iraq will be a cornerstone of stability."
Speaking to Iraqi-Kurdish news outlet Rudaw, al-Nujaifi said that the future federalist structure in Iraq he envisioned entailed "regionalizing the provinces" through the provision of greater self-autonomy.
Al-Nujaifi added that he was working towards the establishment of "a large umbrella for all the important Sunni groups with one which will then be able to represent the Sunnis and could form alliances with Kurds and Shiites".
The establishment of a federal system of government would be beneficial in order to counter perceived Shia domination of state infrastructures, al-Nujaifi also said, claiming that "the Shia are fully running the country by themselves".
Iraq's Sunni community has experienced a declining political role in the post-Saddam era when the dismantling of the Iraqi army and processes of de-Baathification, presided over by Washington, lead to a rise in Shia representation and policymaking in Baghdad.
Sunnis say they face institutional discrimination under the current system and have also expressed concern that Shia militias taking part in current assaults on the IS-held city of Mosul could carry out retributive attacks on Sunni civilians.
A coalition of Iraqi forces – including the Iraqi army, Shia militias known as the Hashd al-Shaabi, and the Kurdish Peshmerga – began operations in Mosul in October.
Although progress has been steady rivalries between the various groups participating in the assault have also contributed to accusations of attempted land grabs.
Al-Nujaifi has previously emphasised that ensuring autonomy for the diverse inhabitants of Mosul, and wider Ninevah province, constitutes a priority in the post-IS era and has held a number of meetings with Kurdish President Masoud Barzani on the issue.
The KRG has said that it could push for independence from Iraq once the battle to liberate Mosul from IS is complete and has been accused of attempting to aportion off land within Nineveh province to fall within its future boundaries.
Since taking Mosul in June 2014, the brutal killing campaigns and repressions of civil and religious liberties unleashed by IS have exacerbated sectarian cleavages, and social divisions in Iraq raising concern that once Mosul falls peace and stability in Iraq will by no means be guaranteed.