A week after authorities in Zambia announced the suspension of customs duty on transmission equipment for television and radio stations to encourage expansion, the country's broadcasting sector is under pressure following a threat by the Minister of Information and Broadcasting Services to shut down Radio Phoenix and pull a programme being aired on the University of Zambia (UNZA) radio.

Minister Chishimba Kambwili has reportedly threatened to close Radio Phoenix saying it is being controlled by the government's main opposition, the United Party for National Development (UPND).

Radio Phoenix had hosted UPND leader Hakainde Hichilema on the programme during which he attacked the Zambian government's economic policy inconsistencies and its failure to address load shedding.

Kambwili said the government has launched investigation into allegations of control and into circumstances behind the dismissal of the presenter of a live phone-in programme 'Let the People Talk' after he (Kambwili) appeared on the programme.

"We have information that the station did not want me to appear on the program to respond to assertions by Hakainde Hichilema the leader of UPND. We will close the station if we establish that it is being controlled by the opposition," Kambwili said.

Radio Phoenix is a privately own radio station and management have yet to comment on the minister's allegations and the threat of closure.

Kambwili is also understood to be pressurising IBA director general Josephine Mapoma to cancel UNZA radio's Lusaka Star, a phone-in programme which features political party leaders and civil society organisations for topical discussions.

UNZA radio is owned by the University and is used for training of students studying mass communication.

The station has also previously been threatened with closure on grounds that management was violating licence conditions in their programming by hosting political party leaders.

While the station was not closed, the government instructed the Zambia Information and Communication Technology Authority (ZICTA) to reduce its radius transmission from 1000 watts to 260 watts.