Those of us who are Conservative Party members have a huge responsibility ahead of us. Who do we elect as the next leader of our great party, and who do we therefore welcome into Downing Street? It’s a choice that will have lasting ramifications, not just for Conservatives but also for our democratic institutions and, vitally, for our United Kingdom.

As Environment Secretary, and more recently as Leader of the Commons, I have served with Boris Johnson and Jeremy Hunt in the Cabinet, and I know them both to be talented and dedicated to a shared Conservative vision.

But, in choosing the next Prime Minister, there are three key questions I have to ask myself. First, who will truly deliver on Brexit and leave the EU, as the British people demanded over three years ago? Second, who will unify our divided nation by upholding a renewed Conservative vision of freedom and opportunity? And third, who will appeal to voters right across the UK, and ensure that a hard-Left Corbyn government never has the chance to wreck our economy?

For me, there is no doubt at all: that person is Boris.

When I look back to the extraordinary days of the EU referendum campaign, I remember standing in a small room in Vote Leave HQ, with Boris and our friend Gisela Stuart, preparing for the TV debates. I remember walking out onto those stages, absolutely certain of Boris’s passionate belief that our country’s future was so much brighter outside of the EU as an independent globally-trading nation, freed from the shackles of EU bureaucracy. If you want to deliver Brexit, you have to believe in Brexit. And there is no doubt that Boris is a passionate believer.

So, our next Prime Minister, in my view, must be a Leave voter who doesn’t just accept the democratic will of the people, but is someone who agrees with it. We need someone who will honour the result of the referendum, and restore the faith that British voters have lost over the last three years in our democratic system. We need someone who will fight tooth and nail to get us out of the EU on the 31st October – “come hell or high water” as Boris puts it – with or without an agreement.

And, as the former Commons Leader, and the person who was in charge of ensuring we got the necessary legislation through Parliament to be prepared for all eventualities, I know that we have taken huge steps right across Whitehall in terms of being ready for our departure on the 31st October. In fact, we were ready to leave without a deal on the 29th March, and we should have done so.

Boris has promised that Britain will leave on the 31st October. He delivered on his promises as London Mayor, and I know he will deliver on his promises as Prime Minister. Under Boris’s watch as Mayor, the murder rate halved, and overall crime fell by 20 per cent; Crossrail was on time and on budget, and tube delays were cut by 30 per cent; over half a million new jobs were created; and over 100,000 new affordable homes were built, more in an economic downturn than Labour achieved in a booming economic period!

He used London’s success to deliver for the lowest paid and most vulnerable – investing in education, homelessness, volunteering and expanding the Living Wage. Whereas, at my weekly Business Questions, all I heard on a regular basis was how badly mismanaged London has become under Sadiq Khan’s Labour control.

As Prime Minister, Boris will bring the same zap and pizazz to No. 10 that he brought to City Hall, and he will be a determined champion for everyone in our society and in all the four nations of our country. He believes passionately in freedom of choice and equality of opportunity; twin pillars in the values of Conservatism.

And, perhaps most importantly, he is the unifying figure who will bring the Tory party back together as we leave the EU on the 31st October. As Margaret Thatcher managed to reach across the political divide and bring people to the Conservative party who had never voted Conservative before, I believe a Conservative party led by Boris will be enlarged and supported by people who are drawn to him, and his clear and positive vision for the future of our country.

Conservative party members face a choice. I know who I’m voting for. I am supporting Boris as my party’s next leader and our next Prime Minister.