The Prince of Wales will deliver the opening address at the COP26 UN climate change summit, Clarence House has announced.
Charles, who gave the opening speech at COP21 in Paris in 2015, will speak to delegates gathered in Glasgow for the opening ceremony on Monday hosted by Prime Minister Boris Johnson.
The Queen announced on Tuesday that she will not attend the evening reception marking the opening of the summit as she will be resting, and she will instead record a message for the world leaders.
Charles, the Duchess of Cornwall and the Duke and Duchess of Cambridge will join the guests at the event to welcome delegates to the summit.
The Queen wants COP26 to be a success and result in meaningful action from the participating nations, and hopes no world leaders will use her absence as an excuse not to attend.
A series of royal events will be staged next Monday, with Charles co-hosting the Great Green Wall session alongside French President Emmanuel Macron and his Mauritanian counterpart Mohamed Ould Abdel Aziz.
The Great Green Wall is an Africa-led initiative to combat desertification by creating a mosaic of green and productive landscapes across the entire width of North Africa.
William and Kate will join Charles to host a reception for key members of his Sustainable Markets Initiative and winners and finalists from William's environmental Earthshot Prize Awards.
The inaugural Earthshot Prize ceremony was staged earlier this month with winners chosen from across the globe, including a project restoring coral reefs and another battling the issues contributing to air pollution in India.
Charles' Sustainable Markets Initiative was launched to help accelerate the world's transition to a sustainable future.
The Queen has been resting following medical advice to cancel her two-day trip to Northern Ireland last week.
But she returned to work on Tuesday, carrying out virtual audiences from Windsor Castle, her first official engagements in seven days, after she was ordered to rest by doctors.
And that evening she spoke on the telephone with Chancellor Rishi Sunak on the eve of his Budget, a tradition dating back some years.
