Madonna will visit Malawi on Sunday to lay the foundation stone of a multi-million dollar girls' school she is building, her charity Raising Malawi told Reuters.

The singer, who has adopted two children from the southern African country, is due to arrive on Sunday and attend a brick-laying ceremony in Lilongwe on Monday. The school is expected to cost about $15 million.

She plans to meet the President Bingu wa Mutharika and together lay a foundation stone for her multi-million dollar girls school, a staffer at the charity, who declined to be named, said on Thursday.

An AIDS epidemic has left over a million children orphaned in the impoverished country of 13 million.

Malawi's government came under fire after Madonna adopted a 13-month-old boy, David Banda, in 2006, with critics accusing it of giving her special treatment by skirting laws that ban non-residents from adopting children.

In June this year, Malawi's Supreme Court overturned a lower court ruling made in April which said Madonna could not adopt a four-year girl -- Mercy James -- because the singer was not a resident of the country.

Madonna last year divorced British film director Guy Ritchie, with whom she has a son Rocco. She also has a daughter Lourdes from her relationship with fitness trainer Carlos Leon.

Malawi