Madonna was visited by Malawi's chief social welfare official on Wednesday.The 'Hung Up' singer, who is hoping to adopt 23-month-old Malawi boy David Banda with her husband Guy Ritchie, welcomed Simon Chisale to her London mansion for the long-delayed assessment.Chisale was later seen leaving the pop superstar's home clutching a blue binder.He refused to comment on the adoption and tried to hide his face as he walked away.The assessment of the couple's suitability to adopt David was due to be carried out by Penston Kilembe, but he was removed from the case after being accused of asking the singer to pay for his trip.Kilembe, director of Malawi's Child Welfare Services, denies any wrongdoing.Earlier this week, Madonna refuted claims Kilembe tried to extort money from her and insisted she hadn't used her "celebrity" to fast-track the adoption.The star's spokeswoman, Liz Rosenberg, said on Tuesday: "The plans to finalise the adoption of Madonna and Guy Ritchie's son David are proceeding as outlined almost a year ago - the day the Malawian government granted them their 'interim' adoption. There has been absolutely no interference with government officials or use of Madonna's 'celebrity' to speed up this adoption as reported."Madonna and her entire family look forward to being granted the final adoption early next year."