Ms May will pledge to put her government “squarely at the service of ordinary, working-class people”, distancing herself from accusations of elitism levelled at the Tories under David Cameron.
Warning against the “ideological templates” of left and right as well as the nationalism of the SNP, she will attack Labour as a “divided and divisive” party obsessed with settling its own internal scores.
In interviews last night, the Prime Minister also sought to soften rhetoric on Brexit, saying she wanted UK firms to be able to trade “within” the single market after leaving the EU.
Responding to the groundswell of anti-establishment feeling that contributed to the vote to leave the European Union, Ms May - who supported the Remain side - will tell Conservative delegates that “a change has got to come”.
“It’s time to remember the good that government can do,” she will say. “Time for a new approach that says while government does not have all the answers, government can and should be a force for good; that the state exists to provide what individual people, communities and markets cannot; and that we should employ the power of government for the good of the people.
“Time to reject the ideological templates provided by the socialist left and the libertarian right and to embrace a new centre ground in which government steps up – and not back – to act on behalf of the people.”
She will add: “If we do – if we act to correct unfairness and injustice and put government at the service of ordinary working people – we can build that new united Britain in which everyone plays by the same rules, and in which the powerful and the privileged no longer ignore the interests of the people.”
Ms May will reject the politics of personality, linking it to the distrust people feel towards elites and arguing government should be about “doing something, not being someone”.
“Just listen to the way a lot of politicians and commentators talk about the public,” she will say. “They find their patriotism distasteful, their concerns about immigration parochial, their views about crime illiberal, their attachment to their job security inconvenient.
“They find the fact that more than seventeen million people voted to leave the European Union simply bewildering.”
The Prime Minister will tell Conservative delegates: “I want to set our party and our country on the path towards the new centre ground of British politics - built on the values of fairness and opportunity - where everyone plays by the same rules and where every single person, regardless of their background or that of their parents, is given the chance to be all they want to be.”
Turning her fire on the Labour Party, Ms May will say they have embraced the “politics of pointless protest”.
“The main lesson I take from their conference last week is that the Labour Party is not just divided, but divisive. Determined to pit one against another. To pursue vendettas and settle scores. And to embrace the politics of pointless protest that doesn’t unite people but pulls them further apart.
“So let’s have no more of Labour’s absurd belief that they have a monopoly on compassion. Let’s put an end to their sanctimonious pretence of moral superiority. Let’s make clear that they have given up the right to call themselves the party of the NHS, the party of the workers, the party of public servants.”
In a series of interviews last night, the Prime Minister insisted she would seek “maximum” access for trade in negotiations with the EU.
“The question is what the relationship we want in the future with the EU,” Mrs May said when asked whether she was intending to take the UK out of the single market.
“I want that relationship to have the best possible deal, the maximum opportunity, for UK businesses to be able to trade with and to operate within that market in the European Union which is the single market.”
Responding to the pound reaching a new 31-year low against the dollar over fears of the economic impact of Brexit, Ms May said “currencies of course go up and down”.
“If you stand back and look at the fundamentals of our economy, which are strong, if you look at the other economic data that has been around in recent weeks, if you look indeed at the most recent forecasts now coming out for growth in our economy this year, all of that is more positive than people had expected it to be and predicted it to be.”