The Economist explains
Why the “WTO option” for Brexit will prove tricky
There are few widely agreed truths in the Brexit debate, but one of them is this: if Britain fails to reach a trade deal with the European Union after Brexit, it will have to fall back on the “WTO option”. This involves trading solely under rules set by the World Trade Organisation (WTO), which govern things like tariffs and quotas. However, in recent months trade economists have reached an uncomfortable conclusion: falling back on the WTO could be a lot harder than it looks. Why?