Her Majesty held virtual meetings with the ambassadors of Libya and the Republic of Congo, where they both presented her with their credentials. The monarch looked beautiful in a stunning floral dress as she received the ambassadors from her oak sitting room in the castle.
The meeting comes just four days before the royal marks the first anniversary of the Duke of Edinburgh's death. Philip passed away on 9 April 2021, just two months before what would have been his 100th birthday.
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It is expected that the Queen will mark the day privately at her Berkshire residence.
Last week, the royal family remembered the Duke in a service of thanksgiving, and the royal ladies all dressed in Edinburgh green, which was Philip's favourite colour.
Her Majesty welcomed the Libyan ambassador, Salal Mrehil
However, when she arrived alongside her son Prince Andrew, the monarch made a quick wardrobe change before she walked inside. She was seen wearing some stylish sunglasses before taking them off and adding a coordinating green hat.
The symbolic choice of green was a fitting way to remember the Queen's late husband as the colour was used over the years for things like his staff liveries and private cars, including the driving carriage at his funeral last April.
She also met the Congolese ambassador, Pascal Gayma
The shade could also celebrate Philip's long-standing association with the Rifles Regiment, who wear a green uniform. The late royal had been Colonel-in-Chief of the Regiment from 2007 until 2020, when he handed over the role to daughter-in-law Duchess Camilla.
At the service, Prince Andrew escorted his mother into Westminster Abbey. The monarch held onto his elbow with her left hand as she moved slowly and gingerly to her place, using a walking stick in her right hand.
They entered via Poets Corner - a shorter route for the Queen's comfort - in a small procession.
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