The military and governors from the south-east moved against IPOB on Friday.
In a statement on Monday, Saraki said due processes must be followed in accordance with the law before such declaration can have effect.
The senate president expressed hope that President Muhammadu Buhari would initiate the right process for declaring IPOB a terrorist group, saying this would demonstrate to the world at large that “we are a country that operates by laid down process”.
“I also wish to state that the announcement of the proscription of the group known as Indigenous People of Biafra (IPOB) by governors of the south-east states and the categorisation of the group as a terrorist organisation by the Nigerian military is unconstitutional and did not follow due process,” the statement read.
“Our laws make clear provisions for taking such actions and without the due process being followed, such declaration cannot have effect.”
Appealing for calm and Nigerians, Saraki called on all Nigerians to come together and find the right solution to the problem rather than worsening the crisis.
“Our brothers and sisters in the south-east, in particular, should continue to maintain peace and tranquillity and go about their lawful business. This crisis will not benefit anybody but would only expose innocent people to unwarranted danger,” it read.
“At this point, Nigerians outside the south-east who have worked to ensure that the crisis does not spread to other parts of the country deserve our commendation. I, therefore, call for continued efforts to sustain peace, unity and stability in all our communities so as to ensure that all residents, no matter their religion, tribe and creed remain protected and safe under the law.
“We must commend the military for their efforts in restoring peace to different parts of the country and sustaining the unity of the country.
“However, in the face of provocation, the military should allow themselves to be guided by their training which emphasises respect for human rights, even in war. Also, giving the nature of this particular situation, the military has every reason to be hesitant in the use of force.”
He said the army should not be over-stretched as there is need to protect the military “against dissipation of their fighting strength”.
The nation’s number three citizen also revealed the plan of the national assembly to embark on a “fact-finding mission” to the south-east.
“I want to also make it clear that the national assembly intends to embark on a fact-finding investigation aimed at determining what actually happened during the period of the military exercise in the south-east. We want to be able to sift the facts from the fiction and determine who did what. It is quite clear that all the facts are not yet known. We assure Nigerians that there will be no cover up. We intend to lay the facts bare.
“We want to remind Nigerians that the reason for embarking on constitution review by the national assembly was to enable us look into issues that are agitating the minds of Nigerians and creating tension among us. We have promised that the exercise would be continuous.
“We intend to keep that promise by further taking decisions that would strengthen and improve on our structures. The eighth national assembly, on resumption, will play its constitutional role by addressing all those issues that are agitating the minds of our people and over which they feel so strong.”