A push by Registrar General Tobaiwa Mudede to ban dual citizenship is part of a plan by the ruling Zanu PF government to rig the 2018 general elections, a local rights group has warned.
The senior civil servant recently addressed a ruling party parliamentary caucus where he urged amendment of the Constitution to ban dual citizenship in a move that would adversely impact millions of Zimbabwe's now living abroad.
Zimbabweans of Malawian and Zambian origin often described by Mudede as "aliens" would also be hit by the development.
Zanu PF legislators were said to be supportive of the proposal.
However, rights group Crisis in Zimbabwe Coalition said the Registrar General should respect the country's constitution.
The group said Mudede proposal was not just an attack on the constitution but also a ploy by Zanu PF to rig the 2018 polls.
"We view the utterances by the Registrar General Tobaiwa Mudede as part of a bigger ploy to disenfranchise Zimbabweans living in the diaspora as we head towards the watershed 2018 elections," said CiZC in a statement.
The opposition has been pushing for a diaspora vote as part of a raft of reforms that must be implemented before next year's elections.
Zanu PF has since made clear its opposition to diasporans voting from their countries of residence while the Zimbabwe Electoral Commission (ZEC) has also said exiles who want to cast their votes must return home to do so.
CiZC condemned Mudede's proposals.
"We are appalled by such undemocratic and discriminatory tendencies by government considering that the new Constitution is a new document which was an outcome of extensive input of the majority including Zimbabweans living in the diaspora."
The group said the Zanu PF-led government needs to recognise and respect the contribution made by non-resident Zimbabweans to the country.
"It is imperative for the government to note that the majority of its citizens are residing globally in countries such as South Africa, Namibia, Botswana Australia, USA and the United Kingdom, among others, and they are now holders of dual citizenship.
"However, these nationals have remained Zimbabweans remitting close to US$2 billion annually.
The group added; "CiZC urges the government to expend its energies on aligning legislation to the constitution and immediately abandon all intentions to amend the constitution barely four years after its adoption.
"Our collective view is that the proposed amendment to Chapter 3 of the Constitution is in similar fashion with the proposed Constitution Amendment Bill No.1 of 2017 which seeks at the rebirth of the Lancaster House Constitution and its undemocratic tenets."