Pub chain Wetherspoon is to sell more drinks from the United Kingdom and non-EU brewers in the run up to Brexit.
Martin - a vocal eurosceptic - said the pub chain is reviewing all of its products in a company-wise reshuffle which could take up to two years, something he hopes will make the business "more competitive".
The EU's customs union is a protectionist system which is widely misunderstood.
He said that tariffs were imposed on wine from Australia, New Zealand and the U.S., and also on coffee, oranges, rice and more than 12,000 other products.
Mr Martin hinted that post-Brexit Wetherspoon's drinks may be cheaper.
Martin is skewing his pubs' ordering of drinks away from European Union sources, because it's cheaper to buy them from outside the European Union and British beers and wines can be purchased without paying the tariffs imposed by the EU's "protectionist system".
Wetherspoon's will honour contracts with several suppliers, some of which last for years.
'However, we are starting to make the transition to non-EU trade now'. It costs a lot to produce, so many publications facing an uncertain future can no longer fund it.
Kopparberg, a popular cider made in Sweden, will still be stocked because production is moving to Britain after Brexit. Hence it's some British sparkling wines instead of champagnes on the drinks list from July, for the extremely small group of people who would choose a Wetherspoons to host the type of occasion where champagne is to be drunk.
It will also sell fewer wheat beers from France and Germany, replacing them with those made by both United Kingdom and non-EU producers across its 880 pubs from Monday 9 July.
Alcohol-free Adnams Ghost Ship will replace Erdinger alcohol-free beer from Germany.
"Champagne has lost market share to lower price sparkling wines", Mr Martin said.
"In the event of Brexit when things are changing, it's a very good opportunity to look around the world and see what we can get that enhance customers' enjoyment of our pubs". A "no-deal" alternative would leave the United Kingdom much better off than it is today'.
He added the government should also cancel the £39billion Brexit bill, which he dubbed a "leaving gift", and invest the money on local projects.