Save the Children UK spokesman Dominic Nutt urged the singer Saturday to "please think twice" before going through with the adoption.
He says he cannot comment directly on Madonna's plans but says adoptions in such contexts are often inappropriate and unnecessary.
Nutt says children are best cared for by their extended families.
A person involved in the Malawian adoption proceedings, speaking anonymously due to the sensitivity of the subject, told The Associated Press on Friday that Madonna plans to adopt a girl there. The recently divorced star has already adopted a Malawian boy.
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