A spokesman for Madonna has previously said that Malawi's President has a "grudge" after her sister Anjimile Oponyo was sacked as the head of her charitable foundation Raising Malawi.
Ms Oponyo was sacked due to "concerns about mismanagement of $3.8m", said Trevor Neilson, whose Global Philanthropy Group manages Madonna's projects in Malawi.
The allegations have been denied by Ms Oponyo and the President Joyce Banda's office has dismissed the claim.
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