The conversation, Rayner told British Vogue, was proof the Labour leader “respected my position”.
Rayner revealed she discussed the matter with Sir Keir at the time Boris Johnson fell seriously ill during the Covid pandemic.
She said: “One of the first meetings we ever had was when [Johnson] was seriously ill with Covid. Keir discussed with me how I’d lead if he fell ill. That really told me he respected my position.”
In further comments on her and Starmer’s relationship, she said: “I think we complement each other because we’re very different. If I was just, ‘Yes, everything you say is wonderful,’ you wouldn’t get feedback. Same with him to me.”
She added: “Our leadership has evolved, like any team when you’re thrown together. Whatever the office politics is like… we understand each other now.”
Rayner, who serves as shadow deputy prime minister and shadow levelling up, housing and communities secretary, previously told the BBC’s Today programme in August that she compares her and Starmer’s relationship to an “arranged marriage”.
She said: “I often talk about it as an arranged marriage. We were both elected by the membership differently and independently. We work constructively together.”
The Labour leader and his deputy have had reported disagreements in the past, including Starmer’s reported attempt to demote Rayner during a botched reshuffle in 2021 following the party’s loss in the Hartlepool by-election.
But what followed was a significant promotion as Rayner, formerly Labour Party chair and national campaign coordinator, emerged with an elaborate 24-word job title as deputy leader, shadow first secretary of state, shadow chancellor of the Duchy of Lancaster and shadow secretary of state for the future of work.
She was also officially made shadow deputy prime minister.
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