The 'Mary Poppins Returns' actress suffered from a speech impediment in childhood and she admitted she sometimes still struggles to not have her words get "stuck", particularly when feeling nervous or under pressure.

"Certain words will get stuck, the phone is a bit of a nightmare... Environments challenge me if I'm scared, or if I'm under pressure to persuade or convince, like, don't ever ask me to pitch you anything ever. A stutter is like an imposter living in your body. Who doesn't pay rent. And completely and utterly misrepresents who you are as a person," she said on stage at Variety's Power of Women gala.

The 40-year-old actress was honoured at the gala with the Wells Fargo's Power of Women Alumni Award for her work with children at the American Institute for Stuttering and she admitted she felt "grateful" to shine a light on the organisation.

She said: "I am grateful to shed light on (stuttering) because it is a disability that lives very often in the shadows alongside its friends, fear and shame and humiliation."

The actress called for people to stop assuming a stutter is down to a nervous condition or a psychological problem, reports aceshowbiz.com.

Highlighting that around 80 million people around the world are affected, she said, "This is wrong. It is neurological, it's biological, it's often hereditary and it's not your fault."

After reflecting on her 17 years' working with the institute, the 'Devil Wears Prada' actress then called on people to "be patient" when speaking to those with communication difficulties. She said: "Next time you meet someone who stutters, know that every word they say takes effort and courage. Look them in the eye, be patient."

"Don't tell them to slow down, or breathe, or spit it out. It's a neurological thing, it's sort of a motor pathway thing. Don't finish their sentences. They know what they want to say, they have so much to share. Just be patient."