The Queen meets ambassadors via video link, her first engagement since contact with Prince Charles.
The Queen has carried out her first official engagements since coming into contact with the Prince of Wales, days before he tested positive for Covid.
Last week Buckingham Palace said the Queen had shown no Covid symptoms and she continued with her work diary by holding virtual audiences from Windsor Castle on Tuesday.
She spoke to the new Spanish and Estonian ambassadors via video-link.
They attended Buckingham Palace for the event.
Prince Charles met the Queen two days before he tested positive last week, while the Duchess of Cornwall has also tested positive for the virus and is self-isolating.
Last week Buckingham Palace declined to say if the Queen had the virus on medical privacy grounds, only stating she had no symptoms.
During the virtual engagement, the new Estonian ambassador Viljar Lubi and Spanish counterpart José Pascual Marco MartÃnez were greeted by the Queen and presented their Letters of Credence to her.