Will Brexit Affect Britain's Ties With Allies And NATO?

Britain has delivered formal notification of its decision to leave the European Union, after 44 years of membership.

The British ambassador in Brussels handed over a letter invoking Article 50 of the Lisbon Treaty, to President of the European Council Donald Tusk.

The document, signed by Theresa May last night, sets out her broad vision of how she sees the process unfolding over the next two years.

As the letter triggering the formal Brexit process was being handed in, Theresa May told MPs in the Commons during Prime Minister's Questions that Britain's commitment to European defence remained firm.

But how much does such a relationship really matter in Germany - the European Union's most powerful country? In the video above Forces News' Rob Olver has been taking a look.

British troops have exercised and operated alongside European Union troops around the world since Britain first joined what was then the European Economic Community in 1973.

Former First Sea Lord, Admiral Lord West, told Rosie Laydon leaving Europe won't affect military partnerships, although he has concerns about the impact on Britain’s territorial waters. He said:

"We've had bilateral exchanges and operations, and worked with nations in Europe for many, many years, before the EU and [the] Maastricht [Treaty] happened... and that will continue, I have no doubt. It's in the interest of Europe."

"Where I see an extra load for us, which is tricky, is actually the close protection of our inshore waters from... terror, smuggling, bringing of arms... That is not well co-ordinated at the moment within this country.

"We are in probably the most chaotic world I have known in my 51 years. You just look around the world and can see threats everywhere, and having strong defence forces stop wars. In a global context they give global stability.

"I do believe this government has taken their eye[s] off that all [having a strong Armed Forces] and they really need to think about where their priorities for spending."

"You can always afford in any country the things you want to afford. What it means is moving things around.

"For example do we want quite so much on aid or would we like to put a little more into ensuring the British people can do the things they think they are able to do -but I'm not so sure they can."