No running with scissors!

Prince Harry had a special helper Wednesday morning to kick off the upcoming London marathon.

Prince Harry Opens The 2017 Virgin Money London Marathon Expo
Credit: Samir Hussein/WireImage

When the royal was handed a pair of scissors for the ribbon cutting at the Virgin Money London Marathon Expo in London, he turned to 5-year-old Melissa Howse.

“Do you want to do it?” he asked the stunned little girl, whose father, Tony, is among the thousands of charity runners who will take to the streets of London this weekend.

After helping her make the snip, he then stepped away before remembering he’d left the scissors in her hands — and his momentary panic sparked laughter.

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“You did a great job, you know,” he told Melissa afterward.

“It was totally unexpected. Neither of us had any idea Melissa would become a princess for the day,” her father, a former Lance Corporal in the Royal Green Jackets who is running with the charity Group B Strep Support, told reporters. “It is hugely exciting.”

Added Melissa: “I am going to watch my daddy run at my grandma’s house. It was very exciting cutting the ribbon. I felt like a princess.”

Runners at the event were given welcome packs that included a special blue headband publicizing Heads Together, the mental health charity organized by Harry, Prince William and Princess Kate.

The Virgin Money London Marathon Expo is expected to welcome more than 80,000 visitors through its doors this weekend.