Daisy Goodwin says her breast was groped by Downing Street official at a meeting during David Cameron’s time in office

Downing Street is to investigate claims that an ITV producer was groped inside No 10 by a government official, the prime minister’s spokesman said.

Daisy Goodwin, who created the ITV drama series Victoria, about the former Queen, said her breast was groped by an official in No 10 when she attended a meeting during David Cameron’s time in office.

No 10 told reporters that Theresa May was taking the complaint extremely seriously. “Yes, of course it’s an issue we are concerned about. We have seen the reports. We are looking into it,” the prime minister’s spokesman said.

The spokesman declined to discuss details of the investigation, but said No 10 would investigate. “We will ensure it is properly looked into,” he said.

It is understood Downing Street has contacted Goodwin about the incident and said it would take an official complaint seriously.

Cameron’s spokesman said the former prime minister was alarmed by the allegation. “This is the first he has heard of this. He is alarmed, shocked and concerned, and has made the Cabinet Office aware,” the spokesman said. “As is usual practice, the Cabinet Office will thoroughly investigate any complaint made.”

Goodwin told the Radio Times she went to Downing Street to discuss her idea for a TV programme. The official, who has not been named, was “a few years younger than me”, she said, and made comments about her appearance, telling her sunglasses “made me look like a Bond girl”.

“At the end of the meeting we both stood up and the official, to my astonishment, put his hand on my breast,” she said.

“I looked at the hand and then in my best Lady Bracknell voice said: ‘Are you actually touching my breast?’ He dropped his hand and laughed nervously. I swept out in what can only be called high dudgeon. I wasn’t traumatised, I was cross.”

Goodwin said the stories that had come to light about sexual harassment in Westminster had caused her to see the incident in a new light.

“Now, in the light of all the really shocking stories that have come out about abusive behaviour by men in power from Hollywood to Westminster, I wonder if my Keep Calm and Carry On philosophy, inherited from my parents, was correct?” she said. “The answer is, I am not sure.

“I think humiliating the official was probably the appropriate punishment, but suppose he tried it on with someone less able to defend themselves?”

The first secretary of state, Damian Green, and the international trade minister, Mark Garnier, are both facing inquiries over claims of inappropriate conduct.