Abu Dhabi has made several major changes to its Executive Council, the main body that governs the emirate.

The number of council members has been cut down to 14 from 18 and there have been a number of departures, including three sons of former ruler Sheikh Zayed bin Sultan al-Nahyan and one son of current ruler Sheikh Khalifa bin Zayed al-Nahyan.

The most high-profile change is the departure of Sheikh Diab bin Zayed al-Nahyan, who is no longer the chairman of Abu Dhabi Water & Electricity Authority. He has been replaced by the authority’s new head Ahmed Mubarak al-Mazrouei, who was previously the chairman of Abu Dhabi Health Authority.

Sheikh Diab had been in charge of Adwea since it was founded in January 1999. The consensus in Abu Dhabi is that he has done well at the utility, although Adwea’s reputation has been tarnished recently by Abu Dhabi National Energy Company (Taqa), a public joint stock company in which it holds a 51 per cent stake. The company invested heavily in overseas assets before the global credit crisis of late 2008 and is being sued in the US by its former chief executive officer Peter Barker-Homek for up to $100m.

Sheikh Diab’s full brother, Sheikh Saeed bin Zayed al-Nahyan, has also left the council. Both are sons of Sheikh Zayed and have the same mother.

Sheikh Saeed was appointed as ruler’s representative by Sheikh Khalifa in June this year.

Another son of Sheikh Zayed also leaving the council is Sheikh Tahnoun bin Zayed al-Nahyan. He is a Bani Fatima and a full brother of the council chairman and Abu Dhabi Crown Prince Sheikh Mohammed bin Zayed al-Nahyan. The Bani Fatimas are the sons of former Abu Dhabi ruler Sheikh Zayed bin Sultan al-Nahyan with his wife Sheikha Fatima bint Mubarak al-Ketbi.

Another Bani Fatima, Sheikh Hazza bin Zayed al-Nahyan, has joined the council as vice-chairman.

Sheikh Sultan bin Khalifa al-Nahyan, the son of the ruler Sheikh Khalifa has left the council. His brother, Sheikh Mohammed bin Khalifa Al-Nahyan, remains on the council, but is no longer the chairman of the Department of Finance. The new chairman of the department, Hamad al-Hurra al-Suwaidi, joins the council.

Abu Dhabi restructures its executive council every two years as required by a law dating back to 1974.

The council members are:

1. Sheikh Mohammed bin Zayed al-Nahyan
2. Sheikh Hazza bin Zayed al-Nahyan
3. Sheikh Hamed bin Zayed al-Nahyan
4. Sheikh Mohammed bin Khalifa al-Nahyan
5. Sheikh Sultan bin Tahnoon al-Nahyan
6. Mohammad Ahmed al-Bowardi
7. Khaldoun Khalifa al-Mubarak
8. Ahmed Mubarak al-Mazrouei
9. Hamad al-Hurr al-Suwaidi
10. Nasser Ahmed al-Suwaidi
11. Abdulla Rashid al-Otaiba
12. Obeid al-Hairi al-Ketbi
13. Moghair Khamis al-Khaili
14. Majid Ali al-Mansouri