The meeting began in typically English style, with talk of the sunny weather. Then Lugovoi steered the conversation round to tea. He suggested they all drink some, joking that the English had cups of tea all the time. Reilly declined and told them he had just drunk water from the cooler. Lugovoi was weirdly persistent.

“They kept on saying to me – don’t you want any [tea], won’t you have any?” Reilly recalled.

Reilly served cups of tea to his three guests. He sat to the right of Litvinenko, who was at the head of the table with his back facing the bay window; immediately across the table from Reilly was Lugovoi. Kovtun sat to Lugovoi’s left. He said nothing. After making tea, Reilly – fortuitously for the would-be assassins – went to the loo.

We don’t know how the polonium was deployed. The forensic evidence suggests that either Lugovoi or Kovtun slipped it into Litvinenko’s tea. For the next 30 minutes, the tea sat in front of him, a little to his left – an invisible nuclear murder weapon primed to go off. Lugovoi and Kovtun must have been barely listening to the conversation: for them, the only question was, would Litvinenko drink?

Litvinenko didn’t drink. One can only imagine what must have been going through Lugovoi’s and Kovtun’s minds when the meeting broke up, his drink untouched.