Prince William has spoken of how he was left with a “very depressing” feeling when dealing with families losing their loved ones during his time as an East Anglian Air Ambulance pilot.

The Duke of Cambridge said the things he saw during his period in the role between 2015 and 2017 were "quite a burden to carry and feel" and made him "think death is just around the door".

In a documentary on mental health being screened on BBC1 this weekend, the Duke said he found the emotional side of being an East Anglian Air Ambulance pilot "very difficult".

In a number of incidents he attended in the region, he said was there were "particular personal resonations with the families that I was dealing with" - a possible reference to the death of his mother, Diana Princess of Wales, in a car crash in 1997.

He said it was particularly hard to deal with having come from the military, where he felt people's feelings were put to one side.

MORE: Prince William reveals he was taken 'over the edge' while flying air ambulance

The father-of-three added: "To then go in to the ambulance world, which is a much more open and actually, in some cases, very raw, emotional day-to-day stuff, where you're dealing with families who are having the worst news they could ever possibly have on a day-to-day basis, it leaves you with a very depressing, very negative feeling, where you think death is just around the door everywhere I go.

"And that's quite a burden to carry and feel.

"And I felt that with a few jobs that I did, where there were particular personal resonations with the families that I was dealing with.

"That raw emotion, I just thought listen, I can't - I could feel it brewing up inside me and I could feel it was going to take its toll and be a real problem. I had to speak about it."

'Pain like no other'

In the documentary A Royal Team Talk, which is being shown on Sunday at 10.30pm, he also spoke candidly about the death of his mother and said there was "pain like no other pain" following his bereavement.

He said it meant he could relate to others who suffered bereavement, adding: "I've thought about this a lot, and I'm trying to understand why I feel like I do, but I think when you are bereaved at a very young age, any time really, but particularly at a young age, I can resonate closely to that, you feel pain like no other pain.

"And you know that in your life it's going to be very difficult to come across something that's going to be even worse pain than that.

"But it also brings you so close to all those other people out there who have been bereaved."

William: We need to talk about our emotions

William said the characteristic "British stiff upper lip thing" had its place when times were hard.

However people also need "to relax a little bit and be able to talk about our emotions because we're not robots", he said.

In the programme William teamed up with Peter Crouch, Thierry Henry, Danny Rose, Jermaine Jenas and England manager Gareth Southgate as they shared issues they have struggled with in their careers in a discussion about the importance of mental fitness.