Kemi Badenoch claims Scottish Labour leader 'actively supports' IndyRef2

The Conservative Party leader also criticised Prime Minister Andy Burnham for having “clumsily opened the door” to another vote during her party conference speech.

Mrs Badenoch also vowed to slash inheritance tax during her speech in Birmingham.

She was introduced by Aberdeen South MP Douglas Lumsden, who won SNP cabinet minister Stephen Flynn’s old seat in July.

Mrs Badenoch said: “This summer, while everyone else was squabbling over a by-election in Makerfield, a byelection about one man's job, Douglas Lumsden fought to campaign in Aberdeen South for thousands of people's jobs.

“Together, we fought to put the interests of the great city of Aberdeen first, and the people heard us.

“Douglas didn't just win Aberdeen South, he won 50 per cent of the vote.

“Conservatives hadn't won a by-election in Scotland in nearly 60 years.

“Last time we were in opposition, it took us 11 years to gain a seat in a by-election. This time, we did it in less than two.

“Douglas won because we understood what was wrong, and we had a plan to put it right.

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“We made it clear whose side we were on, we fought for them, and we are going to do that everywhere in our country.

“Conference, I told you that we have a fight on our hands. There are separatists running not just Scotland, but Wales and Northern Ireland too.

“Our Prime Minister clumsily opened the door to a second Scottish referendum, while his leader in Scotland actively supports one.

“Only the Conservatives will fight properly for our union, and Russell Findlay and Darren Millar are on the front line of that fight.

“I am proud to have them leading our parties in Scotland and in Wales, and we need to give them all our support.

“Aberdeen South shows that we can win wherever we get our message across.”

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Mrs Badenoch’s main pledge in the speech was to abolish inheritance tax on all “family homes” and allow couples to leave behind an additional £1 million tax-free.

The move would mean the number of families paying inheritance will fall by more than a half, Mrs Badenoch said.

She said: said: “Let’s go back to first principles – what is the thing that most people want to pass on to their children and grandchildren? It is their family home.

“Conference, the Conservatives are and always have been the party of home ownership.

“We understand why putting roots down and having a stake in society matters – our homes are where we watch our children take their first steps.

“They are where we gather every Christmas to put up the same decorations – passing on your home to your family is one of the most human instincts of all.

“So, conference, the next Conservative government will legislate so nobody will ever pay inheritance tax on their family home.”

She said that her ambition is to abolish inheritance tax altogether - although she said this could not be done at the moment because of the need for increased defence spending, more prison places and to reduce the national debt.

She said: “But that’s not all, on top of that couples will be able to leave an additional £1 million tax-free.

“These changes mean every inheritance tax bill will be cut and the number of families paying inheritance tax will fall by more than half.

“My ambition is to abolish inheritance tax altogether, as soon as we can afford it. That can only happen with a Conservative government.

“I believe the people who work hard and save should be rewarded for that effort. So, this is my guarantee: no stamp duty when you buy your home, no mansion tax when you live in your home, and no inheritance tax on your home when you pass it to your children or grandchildren.

“That is what the next Conservative government will deliver.”

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Mrs Badenoch, who is black, also criticised Reform UK for “questioning” whether non-white people were English.

She said: “I don't want to live in a country run by people who threaten journalists, who call veterans traitors, and debate whether my mixed race children are English.

“I don't want to explain to my son when we're watching our brilliant England team play football that some people don't think our black players are English.

“I remember back in the day when Ian Wright and John Barnes were playing. Nobody was questioning whether they were English, we certainly didn't have sitting MPs questioning whether they were English.

“We must not let these people take us backwards. That is not the country we are.

“Reform MPs are openly questioning people's identity. They are not like us. We are not like them. We are different. We are the Conservative Party.

“Back in the day, we were the ones who put out a poster saying ‘Labour says he's black, we say he's British.’ We are still that same party.

“I don't know whether you've noticed, but I am black. I am British. I am proud of my country.

“I'm proud of our history, all that we have done, and all that we will do in the world, our best days are not behind us and we will not let this country go backwards.”