Prince Harry had Sunday lunch with the Queen at Windsor Castle

By Heather Cichowski, with files from Danielle Stacey

Prince Harry has been busy since arriving back in the UK last week.

His first visit was to Edinburgh on Feb. 26, where he attended a summit for Travalyst, his new environmental tourism initiative. Two days later, he participated in a recording session with Jon Bon Jovi and the Invictus Games Choir to benefit the Invictus Games Foundation at Abbey Road Studios in London.

And amidst all the bustle, he still made time to see his grandmother, the Queen. Harry and Her Majesty reportedly had Sunday lunch on March 1 at Windsor Castle, according to HELLO! UK. Earlier in the day, the 93-year-old was photographed as she attended the Sunday service at All Saints Church in Windsor.

Prince Harry, Jon Bon Jovi and members of the Invictus Games Choir recreate the iconic Abbey Road zebra crossing photo made famous by The Beatles! Photo: © Samir Hussein/WireImage

Harry reportedly walked from his UK residence of Frogmore Cottage in Windsor to the castle, where he and the Queen shared a light lunch and discussed the future, per The Sun. The publication reports Queen and Harry spent four hours chatting about the Duke and Duchess of Sussex's upcoming exit from senior royal duties. Her Majesty is said to have told her grandson he and Duchess Meghan will be welcome back anytime.

Their midday meal comes after the Queen showed her support for Harry's Invictus Games recording engagement with a little help from the Scots Guards Band during Changing of the Guard at Buckingham Palace on Feb. 28. While Harry was recording the new "Unbroken" single with Jon Bon Jovi and the Invictus Games Choir, the Scots Guards Band played a medley of Bon Jovi (the band)'s hits, including "Livin’ on a Prayer."

MORE: Archie will stay in Canada during Prince Harry and Duchess Meghan's return to the UK: report

Her Majesty has also been busy with engagements herself. She had an appropriately secret outing to MI5 in London on Feb. 25. She took a tour of the museum and was given a private intelligence briefing.

The Queen visited MI5 on Feb. 25. Photo: © Victoria Jones - WPA Pool/Getty Images

Harry and his grandmother likely had a lot to discuss given their busy schedules of late. It was likely a happy reunion for the pair because the duke has been spending the last few weeks in Canada with Meg and their son Archie.

Harry is also winding down his duties as a working senior royal. He and Meghan have a series of individual and joint engagements in the coming days. Harry and Meghan's final joint outing as senior members of the Royal Family is scheduled for March 9. They will attend Commonwealth Day services with members of the family. Then the Duke and Duchess of Sussex will officially step down from their duties on March 31.

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