Each Belgian Stamp is also been issued in a black and white proof sheet with dry cancellation of the Belgian Post. There are only 23 copies of this proof stamps. These sheets are known as Ministerial Sheets since only Ministers of the Belgian Government were entitled to get them. Below are these shown in 'photo' quality since in scanned format, you cannot depict the dry cancellation of the Postal Authorities.
Ministerial sheets are hard to get.