New Zealand Prime Minister Jacinda Ardern has had a private audience with the Queen, one of only four new leaders granted the honour, as the monarch called on Commonwealth leaders to appoint her son Prince Charles their next head.
Ms Ardern said she felt exceptionally lucky to have met the Queen privately. She was one of just four new Commonwealth leaders to be given the honour.
She said her discussion with Queen Elizabeth focused mostly on New Zealand, but would not reveal details about what was discussed.
"She obviously has a huge interest in how we're recovering from the many and varied things that we've been up against in recent times, and clearly maintains a great interest."
She did admit her impending motherhood was on her mind ahead of the conversation.
"Here is a remarkable leader who has conducted her life in the full view of the public and that has included raising her children - and there's something to be admired in that."
Ms Ardern gave the Queen food items from New Zealand as a gift - as well as a photo.
"The personal gift I gave her was something that was sent into my office a few weeks ago," she said.
"It's a photo that was taken by a woman who's now in her late 70s but at the age of 14 took a photo of the Queen as she travelled through New Zealand in the early 1950s.
In return, the Queen gave Ms Ardern two framed photographs of herself.
Ms Ardern is in the UK for the Commonwealth Heads of Government Meeting (CHOGM), and spent much of the day at Buckingham Palace.
She and partner Clarke Gayford were attending a dinner this morning (NZT) along with members of the royal family and the 53 leaders from the Commonwealth, and has been selected as one of two leaders to give a toast.
She said it was "certainly" an honour to be asked to toast the Commonwealth. Ghana's prime minister Kwame Nkrumah has been chosen to toast the Queen.
"You'll see in my comments [I'll be] focusing on the thing that motivates me in politics, which is putting people at the centre of everything we do."
Meanwhile, in an unusual move while officially opening the CHOGM, Queen Elizabeth - who turns 92 tomorrow - called on the Heads of Government to name her son Prince Charles as their next head.
"It is my sincere wish that the Commonwealth will continue to offer stability and continuity for future generations and will decide that one day the Prince of Wales will carry on the important work started by my father in 1949."
The role is not inherited, and will not pass automatically to the Prince of Wales on the Queen's death. The leaders are expected to decide on a successor today.
The leaders gathered at Buckingham Palace are expected to sign off the deal when they meet on Friday. There had been some suggestions that the position should be rotated around member states.
The Queen told the leaders of 51 nations assembled in Buckingham Palace she took great pride in seeing the Commonwealth flourishing.
She welcomed them to the first of two days of events.
"Having on so many occasions been welcomed to opening ceremonies around the Commonwealth, it is my pleasure this time to welcome you to my own home."
Earlier, Prince Charles told attendees the modern Commonwealth had a "vital role to play", adding: "I pray that this [meeting] will not only revitalise the bonds between our countries, but will also give the Commonwealth a renewed relevance to all its citizens."