Saudi Arabia is the last country in the Gulf Cooperation Council -- which includes Bahrain, Kuwait, Oman, Qatar and United Arab Emirates -- to change the Thursday-Friday weekend to be closer to the world's Saturday-Sunday weekend.
King Abdullah bin Abdulaziz issued the decree on Sunday following a recommendation in April by the country's Shura Council or the Consultative Assembly.
The move brings the workweek in Saudi Arabia, the world's largest oil exporter, in line with other countries in the region which already have Friday-Saturday weekends.
The weekend switch will be implemented by schools and universities from the start of the next academic year.
According to the decree, the change was made to better serve "the Saudi economy and its international commitments" and coordinate with the workweek in Saudi Arabia and the rest of the world.
It will "reduce the negative repercussions on economic and financial activity in the kingdom and make up for lost economic opportunities," the decree said.