The privately-owned company will provide about MAD3.2bn from its own resources and raise the remaining MAD1bn from a consortium of seven Moroccan banks.
Both Meditel and its only rival, Maroc Telecom, are expanding their networks to provide services to a series of massive new tourist developments in the south of the country.
Meditel had 6.2 million customers at the end of 2007. Maroc Telecom had 13.3 million.
The two largest shareholders in Meditel are Spanish telecoms giant Telefonica and Portugal Telecom, which both own 32 per cent stakes.