The Queen told Liz Truss they would be “meeting again soon” in her final official engagement before her death two days later.
The then-prime minister travelled to Balmoral Castle to meet Elizabeth II on 6 September and described the monarch as “frail” but “mentally alert”.
Ms Truss said that she had been summoned to the Scottish palace due to the Queen’s health. However, she found her namesake was “absolutely on top” of things and seemed intent on meeting again.
“She was very, very keen to reassure me that we’d be meeting again soon... It was very important to her,” Ms Truss told GB News.
“She was absolutely on top of what was happening. Although she was physically quite frail, she was absolutely mentally alert.”
Ms Truss added that there was no suggestion the Queen might be about to pass away, which she did two days later on 8 September, aged 96.
At the meeting, the monarch, using a walking stick, was pictured smiling warmly as she greeted Ms Truss in front of an open fire in her sitting room at the castle.
“I was obviously only in the first few days of the job of being prime minister. I was thinking about many different things,” Ms Truss said.
“But the assumption absolutely was that this would be the first of many meetings [with the Queen].
“She was very determined to do her duty, right to the end. We had a very, very good meeting. She was upbeat.”
Liz Truss gave insight into her final meeting with the Queen— (AP)
The former prime minister recounted how she was told of a worsening situation on 7 September – with the postponement of a Privy Council.
“I arrived just before 6pm for the meeting. Everybody was there waiting around and we waited for a few minutes and then the news arrived that the Queen would no longer be able to do the meeting. And that was the first I heard of it. But clearly it was a very ominous sign.”
She said of the day she died: “Things were clearly getting even worse the next day, so it was a dawning realisation I think, not just for me, but for my colleagues, that we were facing (it).”
Ms Truss said she felt “very sad” about the situation, but her mind also turned to the practicalities of the days to come.
When the King held his first weekly audience with Ms Truss on October 12, he welcomed her to the Palace by saying: “Back again? Dear oh dear.”
Mr Truss insisted it was a joke and said the pair were at their third meeting that day.
She paid tribute to the late monarch as a major figure for Britain who was “still very, very, very loved and treasured”.
“And she was still very much with us until the end, absolutely,” she said.
“And that’s what just struck me about her is that right until that moment, she wanted to be there doing her duty.”