The Duke and Duchess of Cambridge forged Princess Charlotte’s birth certificate and fooled the world for the past nine months, according to a Russian newspaper.

Pro-Kremlin newspaper Komsomolskaya Pravda has published a story that includes claims from other mothers that “if [Kate] gave birth naturally, it was surely some days ago”.

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As with Prince George’s birth, Kensington Palace released the baby’s birth certificate on Tuesday, which clearly states that Her Royal Highness Princess Charlotte Elizabeth Diana was born on Saturday, May 2.

The certificate also notes that her father’s occupation is “Prince of the United Kingdom” and her mother’s occupation is “Princess of the United Kingdom”.

But the women interviewed by the newspaper before the certificate was made public are adamant that “there is nothing which could help a woman, even if she gave birth with the help of the best doctors, stand up five hours after giving birth – and leave the clinic on her feet”.

Going against the Russian women’s claims it was “impossible” that Charlotte was born on Saturday, Kate was spotted driving Prince George to Buckingham Palace for a swim in the days prior to going into labour.

A number of other women also said Charlotte looked too big to be a newborn and that “she is at least three days old”

Readers of the newspaper accused the royal couple of staging the entire pregnancy, calling Kate “an actress from Buckingham Palace theatre”.

“It was a surrogate mother who gave birth but not her. Kate must have been wearing a fake belly showing to the people that she was pregnant,” one reader suggested.

“She did not give birth, I am sure,” said one woman.

“I thought this too – that the baby is at least seven to 10 days old,” agreed another.