The Duke and Duchess of Sussex will later make their first public appearance in the UK since returning for the Queen’s Platinum Jubilee.
The trip comes just days after Meghan’s wide-ranging interview with The Cut magazine in which she said it takes “a lot of effort” to forgive and hinted that she can “say anything”.
The former Suits actress said that “just by existing” she and Harry were “upsetting the dynamic of the hierarchy” before they stepped down as senior working royals in 2020.
Reports suggest the pair touched down on British soil on Saturday but a spokeswoman for the couple declined to confirm their arrival.
They are going to Manchester on Monday for the One Young World summit, an event which brings together young leaders from more than 190 countries.
Meghan, a counsellor for the organisation, will give the keynote address at the opening ceremony.
The pair will also meet a group of summit delegates doing “outstanding work on gender equality”, One Young World said.
Next stop is Germany for the Invictus Games Dusseldorf 2023 One Year To Go event which is taking place on Tuesday, before they return to the UK for the WellChild Awards in London where Harry will deliver a speech on Thursday.
Their visit to the UK will be the first time they have been back in the country since the Jubilee celebrations in early June, when they attended the service of thanksgiving at St Paul’s Cathedral.
The trip falls in the same week the new prime minister is due to be announced and asked to form a government by the Queen.
The monarch will appoint a new prime minister at Balmoral for the first time in her reign.
The 96-year-old, who has faced ongoing mobility issues, traditionally holds audiences with outgoing and incoming premiers at Buckingham Palace.
It is not known whether Harry and Meghan will visit the Queen in Balmoral during their trip.
An article by Sunday Times royal editor Roya Nikkhah included a quote from a royal source which says it is hard to see that what Harry and Meghan are doing “would equate to the values of the Queen, who has never encouraged people to discuss deeply personal family relationships in public”.
When stepping away from their roles as senior royals, Harry and Meghan promised that “everything they do will continue to uphold the values of Her Majesty”.
The newspaper said a source who knows the Queen well said: “She doesn’t want to be on tenterhooks all the time, waiting to see what the next nuclear bomb will be – that will take its toll.”
Meanwhile, security will be at the forefront of Harry’s mind as he travels from his home in California for the high-profile appearances.
The duke is bringing legal action over a decision not to allow him to pay for police protection for himself and his family when in the UK.
This summer he won a bid to bring a High Court claim against the Home Office.
His challenge concerns the February 2020 decision of the Executive Committee for the Protection of Royalty and Public Figures (Ravec) over his security, after being told he would no longer be given the “same degree” of personal protective security when visiting.
The royal family has been bracing itself for Harry’s forthcoming tell-all book, which he has vowed will be an “accurate and wholly truthful” account of his life.
The memoirs were expected to be published in late 2022 by Penguin Random House but a release date has yet to be confirmed.
There will be concern in royal quarters that the duke will delve into his rift with his brother the Duke of Cambridge, his troubled relationship with his father the Prince of Wales, his view of stepmother the Duchess of Cornwall and the turbulent fallout of Megxit.
Harry and Meghan accused the royal family of racism in their controversial Oprah Winfrey interview last year, saying an unnamed royal made a racist remark about their son Archie before he was born, and that the institution failed to help a suicidal Meghan.
It is thought unlikely the couple will be joined by their children Archie and Lili on the working trip.
The youngsters travelled with their parents to the UK for the Platinum Jubilee and Lili celebrated her first birthday at Frogmore Cottage in Windsor, but Archie and his younger sister did not attend any public events.
Harry and Meghan kept out of the limelight for the majority of the weekend, with the Queen deciding only working royals should grace the Buckingham Palace balcony during the historic festivities.
The Sussexes renewed their lease on Frogmore Cottage earlier this year.
If Harry and Meghan are staying at their UK base, they will be just minutes away from the Cambridges, who are believed to have relocated to their new home, Adelaide Cottage, on the Windsor estate.
The location of the Cambridges’ new home raises the chances of a private meeting between Harry, Meghan, William and Kate, despite their troubled history.