'I feel very honoured – very honoured and very touched'
It was the first time the 74-year-old had spoken publicly about the honour since it was announced at the weekend as the Queen marked 70 years since she acceded to the throne.
The duchess made the comments as she marked the opening of a west London community kitchen.
During the tour, Camilla was asked by a visitor, who gave his name as DJ, how she felt about the title.
The duchess replied: “I feel very honoured – very honoured and very touched.”
Camilla was visiting the Nourish Hub kitchen in Notting Hill, west London, to mark its opening as the royal patron of Harvest UK, the charity which runs it.
The Queen used her Platinum Jubilee message on Sunday to express her "sincere wish" that Camilla will be known as Queen Consort when Prince Charles becomes King.
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In the written message to mark her 70-year reign, the monarch said: “And when, in the fullness of time, my son Charles becomes King, I know you will give him and his wife Camilla the same support that you have given me; and it is my sincere wish that, when that time comes, Camilla will be known as Queen Consort as she continues her own loyal service.”
Charles and Camilla were “touched and honoured” by the Queen’s gesture, Clarence House said.
In a written message, marking the Queen’s Accession Day anniversary, Charles said he and Camilla were “deeply conscious” of the honour.
“As we have sought together to serve and support Her Majesty and the people of our communities, my darling wife has been my own steadfast support throughout," Prince Charles added.
Royal author Penny Junor said the intervention was “an endorsement from the top”.
“This is the Queen’s wish. This is not about Charles being headstrong and wanting this for the woman he loves,” Ms Junor said.
“It is a proper endorsement from the top and it’s right and well deserved, and just as it should be.”
Describing it as the “perfect” way for the Queen to mark her Platinum Jubilee, she added that the monarch was being realistic by setting out plans for the next royal age.
“The Queen is realistic. She’s 95 years old,” Ms Junor said.
“It will do a great deal for the mother-son relationship. Charles will be very very pleased.”
Ms Junor said the Queen’s approval for the duchess would lead to the public accepting Camilla being one day known as Queen.
“It had been suggested to me in the past the only way the public would find it acceptable for Camilla to be Queen was for the Queen herself to make it clear this is what she wanted,” she said.