A new poll conducted by YouGov says 51% of respondents don't think it is right that Archie and Lilibet have been accorded the titles.
The couple first used the title of 'Princess' for Lilibet last week as part of the one-year-old's christening announcement. A spokesperson later clarified that the titles were a "birthright" for the couple's two children and the Royal Family's official website showing the line of succession was later updated.
"The children’s titles have been a birthright since their grandfather became Monarch", a spokesperson said. "This matter has been settled for some time in alignment with Buckingham Palace."
Archie and Lilibet became a prince and princess respectively when Charles became sovereign last September because of letters patent created by George V in 1917, which conferred the style on all male-line grandchildren of the monarch.
To undo this, Charles would have had to issue further letters patent preventing the children from using the titles.
The use of prince or princess for Meghan and Harry's children has attracted a great deal of debate and some controversy, with some pundits calling it "hypocrisy" and others noting it is "in line with precedent".
A YouGov poll released on Monday showed that 51% of all respondents thought that the Sussex children shouldn't have the titles, compared with 25% who thought they should.
Conservative voters were far more likely to believe that the couple's children shouldn't use the titles (72%), while those who voted in favour of Brexit were also significantly more opposed (68%).
Labour voters were fairly split between, with 37% saying they should and 35% saying they shouldn't.
Age was another determining factor in the poll, with the amount of respondents choosing 'should not' increasing with age: 44% of 18-24 year olds increasing to 64% in those aged over 65.
The age distribution was more evenly split among those who responded that Archie and Lilibet should be given titles. Both 18-24 year olds and 65+ came in at 22% of respondents, with the largest age group responding positively to the children being given titles being the 25-49 year olds at 28%.
The polling indicates that younger people are far more likely to not have an opinion on the issue - which may indicate that they care less or that they are more open and have less entrenched views than older people.
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