GAZA CITY, Gaza Strip — An official from the militant Hamas group that rules Gaza says the Islamic Palestinian movement will start choosing its secretive, decision-making council and its administrative leadership this week.

The official said on Wednesday that the process should be completed by the end of the month.

All Hamas members can vote for the Shura Council, which in turn elects the administrative leadership, known as the politburo. The official spoke on condition of anonymity because he is not authorized to discuss the issue with the media.

The Shura Council has 60 members and the politburo will include more than 20 officials. Elections are held every three years.

Voting is to be held in both Gaza and the West Bank, which is ruled by rival Palestinian Authority of President Mahmoud Abbas.