In recent months human-traffickers have convinced many people from Macedonia to travel to Belgium. Often, these migrants are members of the country's Albanian minority.
The people-traffickers have told them that they can get economic asylum in Belgium. Of course, this is not the case and this is the message that the Prime Minister is stressing during his visit.
Mr Leterme, who is accompanied by the Integration Secretary, Melchior Wathelet (Francophone Christian democrat), says that discouraging a stream of economic migrants from Macedonia to Belgium is the main aim of the visit.
Since the beginning of the year citizens of Montenegro, Serbia and Macedonia no longer need a visa in order to travel to Schengen-countries including Belgium.
Mr Leterme was also expected to visit Croatia ahead of the Belgian presidency of the European Union this autumn, but because of the bad weather this visit can now not proceed. Croatia is expected to be only the second Balkan nation to join the EU.
The Belgian delegation is also heading for Kosovo where a public debate is now in progress on whether or not to join the EU.