State radio in Zimbabwe has reported that the detained MDC politician Roy Bennett is due to be sworn in on Thursday as a junior minister.
Mr Bennett was among a list of junior ministers "advised" to report at noon for the ceremony, Spot radio said.
On Wednesday, a magistrate ruled there was enough evidence for him to face charges, including terrorism, and he was remanded in custody until 4 March.
His party has joined Robert Mugabe's Zanu-PF party in a unity government.
The charges against Mr Bennett - the nominee for deputy agriculture minister - have changed several times since his arrest last Friday.
The Movement for Democratic Change has dismissed them as trumped up.
MDC leader Morgan Tsvangirai himself joined the unity government as prime minister last week.
But correspondents say the detention of Mr Bennett and other opposition activists has raised the pressure on him to show this move was not mistaken.
"On behalf of his excellency President Robert Mugabe, the chief secretary to the office of cabinet Meshack Sibanda wishes to advise the following to report at state house at 12 noon tomorrow," Spot radio said, according to AFP news agency.
Mr Bennett - accused of illegal arms possession and terrorism - was among the list of names that followed.