"Let's wait until, God willing, we agree on the location [of the common central bank] and the other details," he said.
The five GCC states "adopted the monetary union accord, which includes the legal and organisational framework," a statement issued at the end of the Muscat summit said.
"It [the council] also adopted a system governing the monetary council," the statement said.
Inability to decide on the location of the regional central bank, which will be independent from the governments of member countries, has been an obstacle to the plan for years.
The United Arab Emirates, Qatar, Bahrain and Saudi Arabia have all expressed interest to host the bank.
The GCC nations are seeking better coordination on economic policies as the oil price has dropped and the global financial crisis has hit the region's economic boom.