Sir Paul McCartney and best-selling author Tina Brown reflect on Queen Elizabeth's unprecedented reign in "Her Majesty The Queen: A Gayle King Special." The special airs on the Queen's Platinum Jubilee, Thursday, June 2 at 10 p.m.ET on CBS and will stream on the CBS News app and Paramount+ on Friday, June 3.

Prince Harry and Meghan Markle are in the U.K. to celebrate Queen Elizabeth's Platinum Jubilee, marking 70 years since she ascended the throne. It is their first public visit to the country since they quit as senior royals more than two years ago.

Harry and Meghan stepped down as senior members of the royal family in January 2020,shortly before the coronavirus pandemic began, and they have largely remained in the United States since. Harry has visited the U.K. a few times, including for the Duke of Edinburgh's funeral last year, and Meghan has reportedly visited once.

The couple observed Thursday's Trooping the Color event in London from the Major General's Office overlooking Horse Guards Parade.

They did not appear on the balcony of Buckingham Palace, after the queen previously said that only working members of the royal family would join her there to inspect the troops and observe a military fly-by as part of the traditional ceremony.

Meghan Markle is seen in a car in central London during Queen Elizabeth II's Platinum Jubilee celebrations on June 2, 2022. Reuters

The couple is expected to attend a service of thanksgiving at St. Paul's Cathedral on Friday, and a concert at Buckingham Palace on Saturday evening.

Prince Andrew was also expected to attend the service at St. Paul's Cathedral, but those plans changed after he tested positive for COVID-19 on Thursday.

There are reports that the queen may meet Harry and Meghan's daughter, Lilibet, for the first time on Saturday, instead of attending a scheduled horse racing event.

The group will reportedly celebrate Lilibet's first birthday at Frogmore Cottage, where Harry and Meghan are staying during their time in the U.K.

Editor's note: An earlier version of this article indicated Harry and Meghan had appeared on the balcony at Buckingham Palace due to a typo. It has been corrected

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