The Channel Islands: Caught in the Brexit crossfire

The Channel Islands were never members of the EU and are thus exempt from the bulk of EU rules

As two British gunboats face off with French fishing boats determined to blockade Jersey's biggest port, we look at the Channel Islands, the eye of the latest Brexit row.

Jersey, Guernsey and their sprinkling of adjacent islands have a combined population of 165,000 who are British citizens.

However, the islands are not part of the United Kingdom.

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Classified as Crown Dependencies, they recognise Queen Elizabeth II as their head of state. London is also responsible for their defence and international diplomacy.

But they do not send representatives to the British parliament and are administered by their own assemblies and governments.

The islands also have their own tax and legal systems.

The Channel Islands are much closer to France than Britain, lying around 22 kilometres (14 miles) from the coast of Normandy and 130 kilometres from southern England.

Part of France's Duchy of Normandy from 933, the islands were incorporated into England when it was conquered by Norman ruler William the Conquerer in 1066.

In 1204 England's King John lost Normandy but retained the Channel Islands, which are known in French as the Anglo-Normandes islands.

They were the only part of the British Isles occupied by Germany during World War II, taken without resistance after the fall of France in 1940. The Germans did not surrender until May 1945.

The largest island is Jersey followed by Guernsey, which has jurisdiction over the smaller inhabited islands of Alderney, Herm and Sark.

Free to set their own tax rules, the islands have a lax system that makes them among the biggest global offshore financial centres in the world.

Jersey alone is the home to more than 400 investment funds looking after £378.1 billion (436 billion euros) and 24 banks with £131.5 billion pounds in deposits, according to Jersey Finance, the sector's lobby group.

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It has a zero corporate tax rate except for companies offering financial services, which pay 10 per cent on profits.

The Channel Islands were never members of the European Union and are thus exempt from the bulk of EU rules.

However they had to follow Britain in leaving the customs union and single market after Brexit -- even though they did not vote in the 2016 referendum.

As well as the row over access to fishing grounds, Brexit has caused problems with supplies to the island.

The extra red tape and EU tariffs particularly affect their key fishing industry, which exports mainly to France.

As the fishing row has escalated, a French minister made a none too veiled threat to cut the electricity supply to the islands, which rely on French power stations.

Despite many of the locals having French names, Britain remains the dominant influence on the island of 100,000 inhabitants, who use British currency and passports and drive on the left.

However a small fraction of the population still speaks the traditional Norman languages of Jerriais and Guernesiais, both close to French.

The islands' most famous exports include Jersey Royal potatoes, Jersey cows, TV detective series Bergerac, Superman actor Henry Cavill and former England footballers Matt Le Tissier and Graeme Le Saux.