Tradition dictates that the first leader to speak is always from Brazil, followed by the host country, the US

Brazil kicks things off because in the early days when no country volunteered to go first, the nation often put itself forward as the first speaker. This has since become tradition.

When the US and Brazil have had their say, every other country’s leader or representative, will have their chance. They can use any of the UN’s six official languages: Arabic, Chinese, English, French, Russian or Spanish.

Speakers are asked to keep their statements to under 15 minutes, although this is regularly ignored. Cuba’s Fidel Castro holds the record for the longest speech at four-and-a-half hours, in 1960. Hopefully we won’t be dealing with anything like that today.

As a rough guide, we’re expecting Biden at about 9.45ET /14.45BST and Zelensky at about 12.45ET / 17.45BST.

But we should warn you, these timings slip. They really do.