The Queen has carried out her first official engagements since being told to rest by doctors and spending a night in hospital.
Her Majesty returned to royal duties with virtual audiences at Windsor Castle.
She wore a yellow dress and her three-strand pearl necklace as she met the ambassador from the Republic of Korea, Gunn Kim and separately, the ambassador from the Swiss Confederation, Markus Leitner.
Last week a Buckingham Palace spokesman said she was admitted for "preliminary investigations" - but returned to Windsor Castle at lunchtime on Thursday and "remains in good spirits".
Today's engagement is the first time the 95-year-old monarch has been seen, albeit on a computer screen, since she hosted a busy evening reception for the global investment summit on 19 October.
Buckingham Palace said in a statement that the Queen held two audiences on Tuesday afternoon via videolink from Windsor Castle.
"His Excellency Mr Gunn Kim was received in audience by The Queen today via videolink and presented the Letters of Recall of his predecessor and his own Letters of Credence as Ambassador from the Republic of Korea to the Court of St James's," the Palace said.
"Mrs Hee Jung Lee was also received by Her Majesty."
The statement continued: "His Excellency Mr Markus Leitner was received in audience by the Queen and presented the Letters of Recall of his predecessor and his own Letters of Credence as Ambassador from the Swiss Confederation to the Court of St James's.
"Mrs Leitner was also received by Her Majesty."
The Queen appeared in good spirits in pictures showing her virtual meeting with Gunn Kim, who was dressed in Korean clothing including a traditional hat known as a gat.
It comes after she "reluctantly" cancelled a trip to Northern Ireland last week after doctors ordered her to rest ahead of preliminary tests in hospital on Wednesday - marking her first overnight stay at a medical facility in eight years.
She is currently being looked after by the Medical Household, her expert team of royal physicians.
Next week, the Queen is scheduled to attend events in Scotland as part of a flurry of royal COP26 engagements involving the Prince of Wales, the Duchess of Cornwall and the Duke and Duchess of Cambridge between 1 and 5 November.
According to the Royal Family's website, the monarch is still listed as attending a reception on 1 November as part of the climate change conference.
Sky News' royal correspondent, Rhiannon Mills, said last week that Her Majesty's hospital admission was not related to COVID-19 - and she was back at her desk doing some light work the following day.
Buckingham Palace has not yet confirmed whether the monarch has received her booster coronavirus jab.
Earlier this month, the Queen was seen using a walking stick for the first time at a major engagement during a Westminster Abbey service.
