Throughout much of the 20th century, attempts at unity have been made by various Arab governments. Each attempt has failed or faltered for a number of reasons, both domestic and foreign.
Of late, there have been whispers of a Gulf Union. This latest endeavor was called for by Saudi Arabia during the final weeks of December in a proposal dubbed the Riyadh Declaration. Ever since Saudi King Abdullah bin Abdul-Aziz al-Saud decided to form a “Gulf Union” at the opening of the 32nd GCC Summit in December, the reactions in the Gulf by governments and the public have not been entirely supportive.
On the governmental level, there was a great divide between the Gulf States during the latest GCC Summit held in mid-May. Kuwait and the United Arab Emirates voiced reservations. Qatar and Bahrain embraced the idea. Oman bluntly rejected it. Because of a lack of consensus, it was decided that more time and study was needed regarding the Riyadh Declaration and it was quickly shelved to be discussed at some point in the future...
http://english.al-akhbar.com/content/gulf-union-building-castles-out-fear