"His failure to comply with the requirement to renounce Zambian citizenship by descent within the prescribed period automatically meant loss of Zimbabwean citizenship," Mudede said in court papers, according to the state-owned Herald newspaper.


Passport seized


Ncube had his passport seized last year after parliament passed a constitutional amendment which allowed the government to impose travel bans on "traitors" or those deemed to be harming national interests. He is contesting the decision to strip him of his citizenship.


Analysts say the decision to confiscate the passports of critics is a sign of growing panic within Mugabe's government in the face of worsening economic problems that many blame on the president's policies.


Ncube's newspapers regularly run stories critical of Mugabe's 26-year rule.