In a speech in the North East of England, the Prime Minister will set out her vision of a "great national mission" of a fairer and more prosperous future outside the EU.
She will emphasise the benefits to be run from regaining border controls from Brussels to curb immigration and the opportunities that can be seized from becoming "a self-governing country" once again.
And she will insist that only a strong government under her leadership can ensure that the opportunity presented by Brexit is not squandered.
Theresa May will try and inject some optimism into the Conservative campaign
She will say: "The promise of Brexit is great – the opportunities before us enormous.
"I believe in the British people; I believe that with determination, ingenuity and common sense, we can use this moment of great national change to shape a better future for Britain."
Her speech today will mark a distinct switch in tone for the Tory campaign following criticism that the party's message has been excessively negative and gloomy.
Jeremy Corbyn has closed the gap on the Tories in recent weeks
And the Prime Minister will attempt to check Labour's recent opinion poll revival by returning to the touchstone issue of which leader is the best choice to steer the UK through the EU exit.
The promise of Brexit is great – the opportunities before us enormous
In her speech, Mrs May is expected to say: “We are now 12 months on from the EU referendum, 12 months since the British people voted for a brighter future for our country, 12 months since they voted to leave the European Union and embrace the world.
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“And in one week’s time, they have the opportunity to affirm that decision and secure that brighter future by voting for me to continue as Prime Minister.
“If they do, I am confident that we can fulfil the promise of Brexit together and build a Britain that is stronger, fairer and even more prosperous than it is today.
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“Because the promise of Brexit is great – the opportunities before us enormous.”
Mrs May will argue that voters opted to build an outward-looking "global Britain" when voting to Leave the EU in last year's historic in-or-out referendum.
“It is time to act on their decision. To deliver their will, to respect the decision of the British people and take Britain out of the European Union," the Prime Minister will say.
The Prime Minister will highlight the potential benefit of Brexit
She is expected to add: “But I want to do more than that. I want us to work together to fulfil the promise of Brexit too.
“Because if we get Brexit right, then together we can do great things.
"We can build a Britain beyond Brexit that is stronger, fairer and more prosperous than it is today; a Britain beyond Brexit that is more global and outward-looking; a Britain alive with possibilities, more confident in itself, more united and more secure."
She will promise that, under her leadership, the government can help to build "a country our children and grandchildren are proud to call home."
Mrs May will say: “If we get Brexit right, we can be a confident, self-governing country once again, a country that takes the decisions that matter to Britain here in Britain.”
The Prime Minister will set out her Brexit plan to restore border controls so the immigration system can serve the national interest.
She is also expected to argue that the country can regain control of billions of pounds of taxpayers' money every year by no longer paying "huge sums" to Brussels.
Instead, she will argue the cash can be spent on the country's own priorities including the Tory manifesto proposal of a Shared Prosperity Fund to reduce the inequalities that exist between different regions of the country.
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She will also trumpet the potential benefits of ending the rule of the European Court of Justice over British affairs and the freedom to forge new trade deals with friends and allies across the globe.
Mrs May is expected to say: “Set free from the shackles of EU control, we will be a great, global trading nation once again bringing new jobs and new opportunities for ordinary working families here at home.”
She will also promise to use it to build a better country, saying: “For Britain to succeed we need to be ready to grasp the opportunities ahead, to make the most of every talent and ensure no person or community is left behind.
“And as we come together behind this great national mission – to make a success of Brexit and of the opportunities it brings – we will build a more united country as our shared values, interests and aspirations bring us together.
Mrs May will champion the idea of an outwardly looking global Britain
“This is the prize – the opportunity that is within reach – a stronger, more secure and prosperous nation, abrighter, fairer future for all.
“That is what excites me about the years ahead, what I am working towards, what motivates me to do what I do and put myself at the service of ordinary working people.
“And it’s what makes the decision you face next week so vital.”
She will conclude: “This is my plan for Britain – a plan for Brexit and beyond. But the brighter future we want for our country will not just happen.
“This great national moment needs a great national effort in which we pull together with a unity of purpose and – however we voted in the referendum last June – we come together with a determination to make a success of the years ahead.
“Because together we can do great things. And as I have said many times in the past, people can have faith in me because I have faith in them.
"I believe in the British people. I believe that with determination, ingenuity and common sense, we can use this moment of great national change to shape a better future for Britain. So this is the time to choose.”