GCC has come with several ideas in past but never worked

They are good in dispute... example of 'Monetary Union Plan' which seems to be derailed.

GCC Countries.
1) Kingdoms of Bahrain
2) Saudi Arabia
3) The sultanate of Oman
4) The states of Kuwait
5) Qatar and
6) The United Arab Emirates.

Out of Six only three Countries are in the Monetary Union Plan. 3 pulled out due disputes.