Trappist monks at the abbey of Saint Sixtus in Westvleteren, Belgium, have complained that Dutch supermarket Jan Linders sold bottles of their Westvleteren beer at five times the price charged by the monastery.

The beer is supposed to only be sold at the monastery’s shop and a local pub for personal use. In 2011, the monks broke this rule and granted Belgian wholesaler Colruyt permission to sell its beer commercially. They extended this permission to include Dutch wholesaler Sligro in 2012.

The monastery sells the beer at between €35 ($43) and €45 per crate of 24 bottles. Sligro and Colruyt were permitted to sell the Trappist beer for €27.50 for six bottles.

Supermarket Jan Linders was selling the Westvleteren beer for €9.95 per bottle. This means a case of 24 at the supermarket would cost approximately €239, almost five times more than the monks charge.

It is unclear how the supermarket managed to obtain 300 crates of 24 bottles of the Trappist beer. The monks claim Jan Linders’ move occurred without their consent.

The standard procedure for purchase of Westvletern beer from the Saint Sixtus abbey involves making an appointment for a pick-up slot via telephone and the buyer providing their licence plate number.

Only two crates of 24 bottles can be reserved every 60 days as the monastery is concerned about commercialisation of its beer disrupting the spiritual work of the monks.

A spokesperson for the abbey said: “A price of nearly €10 per bottle goes against the ethical standards and values that the monks face. Every beer lover knows that the Trappists of Westvleteren do not pursue profit maximisation, they only produce as much beer as is necessary to provide for their livelihood. All the profits made go to the abbey charity.”

Jan Linders defended its decision to sell the Westvleteren beer and the price hike.

The supermarket’s marking manager Gineke Wilms said: “The beer was purchased through a number of links, which is why the price was this amount. We emphasised to the abbey that we had really good intentions. We respect the exclusivity of beer enormously.”

The abbey’s spokesperson said: “We especially hope that it will not happen again.”

The abbey of Saint Sixtus produces three types of Westvleteren beer. A 5.8% alcohol by volume (ABV) Blond, an 8% ABV dark beer called eight and twelve, a 10.2% ABV dark beer. The latter has been repeatedly voted the best beer in the world.