Thank you all for being here. And thank you David Cameron, Harriet Harman and Natalie Bennett for what I think you'll agree is an unprecedented - and, frankly, pretty unlikely - showing of cross-party consensus.
We are about to face the most important decision of a generation, and one that that will determine the future of our country.
And the fact we're all here today shows how important we all feel this is. I know, in Europe, Britain can thrive. Together we will be a stronger and more prosperous nation, creating opportunity for future generations, respected all over the world.
I believe in the positive case for Europe. But I cannot stand back and allow the leave campaign to guide us towards economic ruin, because of a campaign based on lies.
How betrayed will people feel if they vote to leave Europe based on the reasons presented by the Leave Campaign, only to see in the weeks, months and years that follow that those reasons were utter, invented rubbish?
You won't find me saying this about the Prime Minister very often, but what he has just said is absolutely right.
It's not just that the Brexit camp won't say what sort of deal we'll get - and what rules we'll have to play by - it's that they will literally say anything and everything.
The list of countries they have claimed we can emulate - Norway, Switzerland, Albania, Iceland, Turkey, Ukraine and all the others… A reminder of how absurd the Leave campaign has become, and that I really need to crack on with my Euro 2016 Panini sticker album.
But seriously, nowhere is Leave campaign's con-trick more pronounced than when it comes to public spending.
Their big red bus says you can save £350m a week, and then spend it all on the NHS. A complete con. And they're still driving it round despite the figure being rubbished by every economist under the sun.
And it's not just the NHS this made-up, magic money is spent on. This dossier shows they have made two dozen different spending commitments.
Want more money for schools? You got it. Roads, railways, houses. Yep. Do you want to pay junior doctors more, increase welfare spending and slash the deficit all in one go? Of course you do.
You can even have more submarines if that is your thing.
How about abolishing prescription charges? Cutting your council tax by more than half? Slashing VAT - and your energy bills too while they're at it.
They have even said they'd spend millions and millions filling in Britain's potholes.
All of which sounds very tempting, especially that last one - filling in potholes is a cause very close to every Liberal Democrat's heart.
But, if you add all these things up, it would cost £113bn.
One hundred and thirteen BILLION pounds.
Another clear as day example of one of their cons was just this week. On Saturday, they said by 2020, we can give the NHS a £100 million per week cash injection. On Sunday, they said we wouldn't leave the EU until after 2020.
So where would this magic money come from?
They are literally making it up as they go along, trying to con the British public along the way.
And that's not the end of it. Every major financial institution - from the Treasury and the Bank of England to the IMF, the OECD and the World Bank - not to mention just about every credible economist in the country, thinks leaving Europe will hurt Britain's economy.
A few days ago the Institute for Fiscal Studies warned that it would leave us up to £40 billion short in the public finances by 2020 - and that's before all that extra magic spending.
It is a black hole at the heart of their spending plans of more than £150bn.
So they've got to come clean to the British public. Will they now disown these commitments and admit this is fantasy economics? That these are lies? That they add up to one, big massive con-trick?
That's why the four of us are here together today.
There's not much we all agree on, but we agree on this:
It's time for the Leave campaign to come clean about what will really happen if we leave the European Union.
It's time for answers.