Celtic's sponsor have been forced to swap branding on their shirts for the club's match against Legia Warsaw tonight - due to Polish national advertising regulations.

Drinks firm C&C Group plc will have to swap branding on Celtic's shirts from its cider brand, Magners, to its lager brand, Tennent's.

The advertising of alcohol brands is generally prohibited in Poland under its anti-alcohol regulations -

but an exception is made for beer brands, which are widely promoted at Polish football matches.

C&C views the Polish legal prohibition as an unreasonable and disproportionate interference with the company's right to commercial expression under the European Convention on Human Rights.

The company has also written to the Scottish Government, the Scottish FA and the European Cider and Fruit Wine Association (AICV) seeking support.

Magners brand owner C&C Group has also protested at what it views as an illegitimate and disproportionate barrier to the free movement of goods within the EU and believes that the privileged treatment of beer in Polish national advertising regulations may constitute an effective barrier to cider producers from entering the Polish market and may also raise other legal concerns, including fair competition, under Polish law.

Paul Condron, Group Marketing Director at Magners, said: "As Celtic's shirt sponsor we feel strongly that we should be free to display the Magners brand on the Celtic shirt in Warsaw. However, because of Polish national advertising rules that prevent cider brands from being promoted at a football match, we have had no choice but to swap Celtic's shirt branding from Magners to Tennent's Lager.

"Polish national advertising rules that allow beers to be promoted in and around Polish stadia and on TV while banning the Magners branding from the Celtic kit are clearly discriminatory. Cider has a similar alcoholic content to beer, it is packaged and drunk in a similar way and is the most comparable alcoholic drink to beer that there is. We can see no rational or persuasive reason for cider to be treated differently from beer, other than to protect the interests of local beer brands.

"C&C Group is committed to promoting its brands responsibly but we view these Polish national regulations as simply absurd."