Police in Lesotho have arrested the country's former first lady over the 2017 murder of the then-estranged wife of recently resigned Prime Minister Thomas Thabane.

Lesotho's court of appeal last week revoked her bail on suspicion that the procedure was not followed correctly and ordered her rearrest.

She was told she would be taken to the female correctional facility in fulfilment of the appeals court judgement.

"The decision of the High Court to grant you bail has been set aside by the Court of Appeal," said the magistrate.

The former prime minister stepped down in May after months of calls for his resignation over the case.