Many of the activists still detained in Zimbabwe are members of Prime Minister Morgan Tsvangirai’s Movement for Democratic Change, which entered into a unity government with Mugabe earlier this month.
One of the highest profile detainees is MDC treasurer- general Roy Bennett who remained in detention pending an appeal by state lawyers against the high court’s granting of bail on Tuesday.
"The release of political prisoners is important not only for the humanitarian (situation) and human rights but also for the national reconciliation process," Ban said after talks with South African President Kgalema Motlanthe.
Bennett, who had been earmarked to become deputy agriculture minister, faces charges of plotting terrorism, insurgency and banditry. He denies the charges.
Zimbabwe’s new government urgently needs to tackle the country’s economic meltdown that has led to the world’s highest inflation, a worthless currency and a cholera epidemic that has killed 3,877 people and infected over 83,000 others.
Tsvangirai said last week it would cost as much as $5 billion to repair the shattered economy.