Saudi Arabia has opened its first liquor store in the diplomatic quarter in the capital, Riyadh, two sources told CNBC.

The news, which has not been officially confirmed by the Saudi government, represents a major achievement for the ultra-conservative Islamic theocracy, where alcohol has been banned since 1952.

According to a list of store rules seen by CNBC, the place is only available to non-Muslim diplomats, and the permit must be verified through an app called Diplo.

No guests or persons under the age of 21 are permitted to accompany authorized visitors into the store, photography is strictly prohibited and cell phones must be kept in secure “mobile bags” so they are not used while in the store. Purchases are also subject to monthly quotas for each registered individual.

Rumors have abounded for years that the Gulf kingdom, known for its ultra-conservative laws, would eventually allow alcohol consumption outside foreign embassies as part of its broader campaign to liberalize Saudi society and attract more tourists and international expatriates. A Saudi advisor close to the kingdom's royal court told CNBC that having a store in the Diplomatic Quarter is a small step in this direction.

“It is a small step to eventually open up alcohol sales to non-Muslims in Saudi Arabia, to hotels and other places,” said the consultant, who requested anonymity due to the sensitivity of the issue.

They added that one of the main goals is “to deal with the smuggling problem that we always have with diplomats.” It is known in Saudi Arabia that foreign embassy employees, who are able to import alcohol to keep on the embassy premises, often import alcoholic beverages in large quantities and then sell them on the black market.

A Western diplomat based in Riyadh, who requested anonymity due to professional restrictions, said their colleagues had already visited the store and that it was “very well equipped.”

CNBC has contacted the Saudi Ministry of Information and Foreign Affairs for comment.

Saudi Arabia has witnessed seismic change both socially and economically in the years since the young Crown Prince Mohammed bin Salman, now the kingdom's de facto ruler, came to power.

His brainchild, Vision 2030, is a multi-trillion-dollar campaign to reshape the Gulf state's image, attract tourism and diversify its economy away from oil.

It has seen a series of liberal reforms implemented since coming to power, allowing previously prohibited things such as women driving, cinemas and concerts, while simultaneously suppressing dissent and imprisoning political activists.

The Kingdom has witnessed the implementation of a series of liberal reforms sSince Crown Prince Mohammed came to power, Saudi Arabia has allowed previously prohibited things like women driving, movie theaters and concerts, while simultaneously suppressing dissent and imprisoning political activists.