Theresa May has said she has "every confidence" that Boris Johnson can achieve a new trade deal with the EU by the end of 2020.

The former prime minister also warned that while the UK's "special relationship" with the US must be preserved, Johnson's Government must not "just accept every position the US takes".

She added that the Government must work "flat out to repay the trust" of former Labour voters who elected Conservative MPs in last week's General Election.

Responding to the Queen's Speech, May spoke of the "huge responsibility" that comes with the Conservative Party's convincing election success.

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Congratulating Johnson for the party's "overwhelming victory", May added: "I have been in this House for over 22 years and this is the largest number of Conservative MPs I have seen in this House."

The National: Boris Johnson addresses the nation from the steps of Downing Street

Speaking about a future trade deal, May said: "There are those who say it cannot be done. I do not believe that. I have every confidence that it can be done."

May also urged Johnson to prioritise voters' jobs in any trade negotiations.

"We must deliver on Brexit and those manifesto commitments but we must go further. We must ensure that with every decision we take in this House we remember those communities who have lent us their vote," she said.

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"It also means remembering those communities when negotiating trade deals around the world including with the European Union, because good trade deals will be ones that protect the jobs of those who have put their faith in us. But more than that, bring good, new, better jobs here to the UK."

May also warned Johnson about the UK's relationship with the US.

"That is a special relationship, a special relationship that we must nurture and preserve," she said.

"But it is not a one-way relationship, we don't just accept every position the US takes. We consider our own interests, and when we believe and disagree with them then we tell them clearly that we disagree with them."

May added that the rules-based international order has "come under significant threat".

She said: "We've also seen some interest from some in stepping back from a defensive democracy, human rights and the rule of law. We have to decide whether to look inward or to continue to play a role in defending those values.

"I believe we should because that is what global Britain is all about. And it is important that we continue to uphold those values around the world."

On Scotland, May warned the SNP that breaking up the Union "is to the benefit of no one and the detriment of all" and that an independent Scotland "will not be in the European Union".

The National:

May welcomed references to the Domestic Abuse Bill and reform of the Mental Health Act in the Queen's Speech, but said she would have preferred a "more full-blooded commitment to a new Mental Health Act" rather than a promise of reform.

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"It's not just about resources, it's about the attitude and way in which people are treated - and if we put those changes into place in a new Mental Health Act, we will genuinely be bringing significant improvements to people in this country with mental health problems," she said.

May also called for an assurance that the Government "does not abandon the work on the race disparity audit" to create "one nation".