The Prince of Wales has described how he and the Princess of Wales approached telling their children about difficult moments they have faced over the past two years, such as Catherine and King Charles' cancer diagnoses.

"We choose to communicate a lot more with our children... most of the time, hiding stuff from them doesn't work", Prince William said during an interview in Brazil.

"Every family has its own difficulties and its own challenges. It's very individual and sort of moment-dependent as to how you deal with those problems", he added.

The prince visited the Latin American country for the first time last week to mark the fifth Earthshot Prize, of which he is the founder and president.

The prize celebrates people who have come up with ideas to help tackle issues affecting the planet. The winners of each category win £1m to further develop their ideas.

Speaking to Brazilian TV host Luciano Huck in Rio de Janeiro ahead of the awards ceremony, which took place on 5 November, Prince William was asked how he and Catherine navigated the difficult things they have faced over the past two years.

"Sometimes you feel you're oversharing with the children", said Prince William, who is father to Prince George, 12, Princess Charlotte, 10, and Prince Louis, seven.

"But most of the time, hiding stuff from them doesn't work, and so explaining how they feel, why that's happening, giving them other viewpoints as to why they might be feeling like they are sometimes helps give them a bigger picture, and they can relax more into it rather than being really anxious about 'what are you hiding from me'?".

"There's a lot more questions when there's no answers."

"But it's always a balancing act", he added, "How much do I say? What do I say? When do I say it? There's no manual for being a parent, you've just got to go with it".

The Princess of Wales revealed she was in remission from cancer in January.

King Charles continues to undergo treatment.

In the interview, which covered a range of subjects, Prince William also said they do not allow their children to have phones.

"It's really hard. Our children don't have phones, I think when George moves onto secondary school then maybe he might have a phone that has limited access," he said.

"It's getting to the point where it's becoming a little bit of a tense issue but I think [Prince George] understands why, we communicate why we don't think it's right, and again I think it's the internet access we have a problem with.

"I think children can access too much stuff they don't need to see online," he said.

He added that either he or Catherine do the school run most days and jokingly referred to himself as a taxi driver when conversing with Huck.

Speaking about the Earthshot Prize, being held in Brazil for the first time this year, Prince William said: "We're halfway through the ten years that we've identified as the decade of change, where if we want to leave a lasting legacy and really change the way we protect and restore and live on the planet we have to do it in this decade of change.

"So am I pleased with the progress the Earthshot has made and where the world is headed in environmental and climate leadership? Yes, I think we've made progress. Is there a lot more to do? Yes."

Winners of this year's prize included a project to restore tropical forests and a global ocean treaty initiative.

Following the trip to Rio, officials announced they would be making Prince William an honorary citizen of the city, known as a carioca.