ANDREA LEADSOM has promised to "banish the pessimists" as her supporters marched on Parliament chanting for the Tory leadership candidate to become the next prime minister.

In what was billed as a major speech on the economy, Mrs Leadsom promised "prosperity, not austerity" and said she would be a "realistic, but optimistic" leader for the post-Brexit age.

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Despite controversy over her CV and attempts by a member of rival Michael Gove's team to keep her out of the run-off vote for party members by urging supporters of frontrunner Theresa May to back the Justice Secretary in the final round of the MPs' ballot today, Mrs Leadsom did not take questions from journalists.

Instead, her campaign chief Tim Loughton and proposer Penny Mordaunt led a march of blue t-shirt clad activists to Parliament, chanting: "What do we want? Leadsom for leader. When do we want it? Now."

In her Westminster speech, Mrs Leadsom signalled she would keep up the momentum of the Leave campaign and focus on voters who feel the political and economic system does not work in their interests.

She committed to ending Chancellor George Osborne's austerity policies, and indicated she would clamp down on chief executive pay.

"I'm an optimist," Mrs Leadsom said.

"I truly believe we can be the greatest nation on Earth.

"As we show that the UK is once again open to the world and united in our new destiny, so we will expand our horizons.

"Prosperity should be our goal, not austerity.

The Herald:

"I want to spread prosperity to every corner of our country, I want to help create more jobs, because we need to hear and heed those millions of our fellow citizens who feel and fear that their country's leaders are not worrying about them enough.

"Those people who think that chief executives of some big businesses get telephone number salaries but bear no relation to the performance of their companies.

"And I say to all of those people - I am with you and I want you to share in the great future for this country."

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At the speech, supportive former Cabinet minister Owen Patterson was photographed with a handwritten list of MPs' names on his lap.

It included those who have yet to declare their support for a particular candidate - including Zac Goldsmith, Rebecca Pow and Sir David Amess, among others.

Meanwhile, Mrs Leadsom reassured voters and businesses that "no-one needs to fear" Brexit and promised continued free trade with the EU while simultaneously controlling immigration.

The leadership contenders are grappling with how to stay in the European single market free trade area while also ending free movement of EU citizens and so controlling immigration, believing that is the mandate given to them by the referendum result.

The two positions have been described as "mutually incompatible" by Foreign Secretary Philip Hammond but supporters of Mrs Leadsom said she would set out a "third way" if she gets through tonight's MPs ballot and enters a run-off with Mrs May.

Mrs Leadsom said: "My first task is to show how great our potential is as a nation, let's banish the pessimists.

"No-one needs to fear our decision to leave the EU.

"We will do so carefully, reassuring our European friends, and those businesses who are worrying about change

"Trade must be the top priority - continued tariff free trade with the EU, continued free trade with those countries we have agreements with as a current member of the EU, and vitally, seizing the opportunities to take up new free trade agreements with fast-growing economies around the world."

She put pressure on Mrs May to guarantee the status of EU nationals in the UK, insisting she would not use people as "bargaining chips".

She said: "We want fair but controlled immigration - fair to those who are already here and fair to all the talents across the world.

"So I tell you today: I will not use people's lives as bargaining chips in some negotiation. People need certainty and they will get it - I say to all who are legally here that you will be welcome to stay."

Mrs Leadsom also promised farmers, universities and others who receive EU money will have it replaced by her government, and told students, scientists and others who travel for work and research: "You will be absolutely free to do so."

Following her speech and the march, Ms Mordaunt promised that Mrs Leadsom would set out a "third way" to solve the apparent dilemma over the single market and free movement.

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The Defence Minister told the Press Association: "If she's on the ballot paper tonight you will see her throughout the campaign outline different elements of this in more detail.

"But what, if you like, the unique selling point of Andrea is, that the other candidates haven't got anywhere near, is that she understands the single market and the free movement issue - but there is a third, and that is restoring certainty and stability."