His comments come at the back of the EC's push for a new voters roll.
The EC in March 2019 announced it will compile a new voters' register for the 2020 elections.
Ahead of that, a limited registration of new voters prior to the District Level Elections and a Referendum will take place in all district offices of the Commission across the country in May.
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The EC argues that the plan to organise the registration at the district level falls in line with measures to upgrade its Information Technology (IT) infrastructure.
Jean Mensa said her outfit would proceed with the registration exercise at its District Offices despite public opposition to the plan.
But the NDC maintained that many potential voters could be disenfranchised.
Asiedu Nketia speaking at a symposium held by the Koforidua Technical University chapter of the Tertiary Education Institutions Network (TEIN) on the theme: 'Current State of Ghana', he said "the EC is “going to conduct an election and you [EC] are enjoined by the Constitution to make sure that every Ghanaian of 18 years and above is registered and would have the opportunity to cast their ballot. Then you intentionally developed a system which will disenfranchise a minimum of 1 million voters, and we are all quiet in this country."
"Where are we heading?" he queried.
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He added that "Before we undertake any registration exercise of voters in Ghana, the first thing you do is – since you are going to register human beings of a certain age, the Electoral Commission is not mandated as an institution to make pronouncement of how many Ghanaians are of this age, the institution that does that is the Statistical Service of Ghana – … write to the Statistical Service [and find out] how many Ghanaians are of 18 years and above as of today, and they’ll give you the figures.
"Even if you go by the most conservative estimate and you assume that nobody grew, all our ages were stagnant at some point in time or nobody gave birth in this country, at least between 2016 and 2019, a period of 3 years, can’t you get one million people who have entered the 18-year group?” he wondered, adding: “Jean Mensa wants us to accept that the number of Ghanaians who have entered the 18-year group and above is 300,000 in three years, so, this type of mathematics can only happen under Nana Akufo-Addo's government."