Rachel Johnson has revealed she will compete in the European elections next month for the newly formed Change UK group.

The sister of the former foreign secretary and prominent Brexiteer Boris Johnson made her surprise announcement as she appeared at the launch of the party’s election campaign.

Rallying against Brexit, Ms Johnson said she did not want to see it “rubbing out my children’s prospects and chances of living and travelling and working in Europe”.

“These are chances that the politicians who decided to campaign to Leave have enjoyed themselves,” she told the Evening Standard.

“It is simply not fair – and sometimes one has to stand up and be counted. It is now that time for me.”

Siblings in politics: Family friendships and rivalries Show all 5 1 /5 Siblings in politics: Family friendships and rivalries Siblings in politics: Family friendships and rivalries The Johnsons Youngest Jo, middle child Rachel and eldest and loudest sibling Boris Johnson have much to disagree over. Jo is a Tory MP who resigned from the government over May's Brexit deal and supports a second referendum. Boris is also a Tory MP who resigned from the Government over Brexit, however, unlike Jo, he led the country into Brexit. Nowadays he agitates for whatever seems convenient for his leadership ambitions from his column in the Daily Telegraph. Rachel was a Tory member who defected to the Lib Dems over Brexit and is now standing in the European elections for new centrist party ChangeUK Rex Siblings in politics: Family friendships and rivalries The Milibands Elder David was a prominent figure in Gordon Brown's government who seemed the likely successor to the Labour leadership after Borwn's departure in 2010, that is until younger brother Ed beat him in the final round of polling and went on to lead the party for five years Getty Siblings in politics: Family friendships and rivalries The Eagles Angela (R) and Maria Eagle were the first set of twins to be elected to parliament back when they both won seats for Labour in the 1997 General Election. Both sisters are still MPs today and have individually held various shadow cabinet roles PA Siblings in politics: Family friendships and rivalries The Chamberlains Both elder Austen (L) and Neville Chamberlain were successful Conservative MPs in the early-20th century. The former being Chancellor and Foreign Secretary and the latter Prime Minister. Their biggest disagreement was over the Nazi threat, Austen argued for rearmament while Neville was in favour of appeasement Getty Siblings in politics: Family friendships and rivalries The Foots Elder Sir Dingle Foot and younger brother Michael were both prominent Labour politicians. Michael served as leader from 1980-83, resigning after losing an election to Margaret Thatcher's Conservatives Getty

Ms Johnson – formerly a campaigner for the Liberal Democrats – will represent the party for the South West region and said she had called her brother Boris to inform him of her decision.

The journalist and campaigner continued: “A vote to leave the EU is so important, so life-changing for the next two generations that I am impelled to stand up and be counted for what I believe in, which is that we are far better in Europe.”

“I’m honoured they have picked me to stand in the South West, which is where I call home. I went to school there, my father was born in Penzance and we have family dating back to the 1600s in my local village.”

Ms Johnson joined dozens of candidates on stage in Bristol for the launch of the party’s European election campaign including former BBC journalist Gavin Esler, ex-Tory minister Stephen Dorrell and QC Jessica Simor.

Support free-thinking journalism and attend Independent events

Mr Esler, who is standing as a candidate in London, slammed Brexiteers such as Nigel Farage and Jacob Rees-Mogg as the “posers of Brexit”, who were simply ”selling the same old snake oil”.

He said: “I have never been seriously worried about the future of our country but I am now.

“Our political system is a joke. It is a worldwide joke. They are laughing at us – not with us, at us.”

Interim leader Heidi Allen said 3,700 people had offered to stand in the elections, with candidates from “every corner of the UK” and from “all walks of life”.

“These elections are a chance to send the clearest possible message – we demand a people’s vote and the right to campaign to remain in the European Union.

“We are not afraid to say it as clearly as that.”

The former Tory MP added: “This is no rebel alliance – this is the home of the Remain alliance.”

Ms Allen also suggested that Change UK could back the government in a no-confidence vote to avoid a damaging general election.

Speaking to The Independent after the launch, she said an election was “absolutely the last thing” the country needed during the Brexit chaos.

She also dismissed questions over lack of clarity on what the party stood for aside from its opposition to Brexit.

“Yes there will be things that we will disagree on, for sure,” she said.

“[Ex Labour MP] Chris Leslie jokes that I am more left-wing on welfare than he is.