Kate told reporters: “I wish her all the very best, I can’t wait to meet her because we haven’t yet met her yet so hopefully that will be soon.”
The duchess and Mrs Biden were visiting an academy school for four to 11-year-olds to highlight the issue of the early years development of children.
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Jill Biden and Duchess of Cambridge visit Cornwall school
It is the first time the two women have met and during the visit they held a roundtable discussion on early education.
They also toured a classroom, meeting some of the younger children at Connor Downs Academy.
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They also brought carrots which were fed by the children to the school’s pet rabbits in the grounds.
On Thursday Mrs Biden was asked about meeting the Royal Family – with the Bidens due to have tea with the Queen at Windsor Castle on Sunday.
She replied: “Well, we’re hoping to focus, I think, on education.
“Joe and I are both looking forward to meeting the Queen. That’s an exciting part of the visit for us. We’ve looked forward to this for weeks and now it’s finally here. It’s a beautiful beginning.”
Mrs Biden and Boris Johnson’s wife Carrie Johnson enjoyed the views over Carbis Bay on Thursday before the politicians carried out their first meeting of the summit.
The Duke and Duchess of Cambridge are starting to make their mark as senior royals with a number of high profile events during the summit.
Later William will join his father to host a reception for the leaders and chief executive officers from some of the world’s largest companies to discuss how the private sector can work with governments to tackle the climate emergency.
The couple will then join the Queen, the Prince of Wales and the Duchess of Cornwall at the G7 leaders reception tonight.