He is then expected to be presented to the media on Thursday.
PAO president Nikos Pateras met with Gilberto's representatives last week and thrashed out a deal after making an offer of around £1million to Arsenal on Friday.
Barring any last-minute changes, the World Cup winner will ink a deal that will see him earn around £6million over the next three years, making him by far the best paid player in the country in a move which will cost Pana almost £8million in total.