Theresa May proposes two-year 'period of implementation' after UK leaves EU - as it happened

May says her Lancaster House speech in January still stands.

Since then, the UK has published 14 Brexit papers and there have been three rounds of negotiations.

She says the UK and the EU have committed to protecting the Good Friday agreement and the common travel area.

And they have said they will not allow physical border controls.

May says the EU and the UK share a profound responsibility to make Brexit work.

(She is using the passage pre-briefed - see 2.03pm.)

May says Britain has chosen to leave the EU, but the UK is still “a proud member of the family of European nations”.

She says the success of the EU is “profoundly in our national interest”.

May says the UK will continue to work with the EU as a sovereign nation, with the British people in control.

That is what the referendum was about.

People want more direct control, she says. They want decisions made in Britain by people who are accountable to them.

That is why the UK has never “entirely felt at home being in the EU”.

The EU never felt “an integral part of our national story”, she says.

Pooling sovereignty can bring great benefits. But it also means countries have to accept decisions they don’t want.

So that is why the UK voted to leave.

May says mass migration and terrorism are two examples of challenges to our shared European values that we can only solve in partnership.

Climate change, and the proliferation of nuclear weapons by North Korea, are other examples of challenges that must be tackled internationally.

These challenges can only be tacked by like-minded people coming together.

Britain has always and will always stand with its friends and allies in defence of these values, she says.

Britain may be leaving the EU, “but we are not leaving Europe”.

May says Britain will continue to lead in Europe on issues that affect security.

May says there is a vibrant debate going on about the shape of the EU.

Britain does not want to stand in the way of that.

We want to be the EU’s “strongest friend and partner”, she says.

• May suggests Brexit may help the EU, because the UK will not block further integration

May says the Renaissance showed us that, if we open our minds to new possibilities, we can forge a better future for our peoples.

That is what she wants to focus on today.

The UK is leaving the EU. It wants to be a global, free-trading nation.

For many people this is a worrying time. But she looks forward with optimism.

Theresa May has arrived.

She says it is good to be in this great city of Florence, at a critical time for the evolution of the relationship between the UK and the EU.

The Renaissance began here. In many ways it defined what it is to be European.

And here is Nigel Farage on the decor.

And this is from the Independent’s Jon Stone.