In most cases if you fly for a local operator you will be required to hold a local license. Occasionally, some countries will validate your foreign license (FAA, EASA).
Go to GCAA website and look under licensing:
Can I receive a GCAA CPL/ATPL issued on the basis of my ICAO CPL/ATPL?
Yes you can. Provided that you meet the licensing conversion requirements detailed in GCAA CAAP 4. It is important to note that at the time of application you will need to submit your original ICAO license, medical certificate and original logbooks. We also require a written license verification statement from the ICAO issuing authority. These and further requirements are outlined in GCAA CAAP 4 paragraphs 7 and 10.