UK approves Covid vaccine

British regulators have judged that the Pfizer / BioNTech vaccine against Covid-19 is safe to be used in the general population, which means a mass immunisation campaign can now begin. It's the first country to approve the vaccine. The UK government says the first 800,000 doses will be available next week. We'll answer your questions on the vaccine with our regular health expert and the BBC health team.

We'll also hear the UN Secretary General Antonio Guterres answer questions from young environmentalists around the world on climate change and the state of the planet. He's given a speech on the BBC in which he warns that "our planet is broken" and the world faces disaster without radical action. We'll play you some of the speech and some of a conversation he had with the naturalist, Sir David Attenborough.

Picture: A dose of the Pfizer / BioNTech vaccine (BioNTech SE 2020, all rights reserved/Handout via REUTERS)