Kiwi actor Julian Dennison talks about his new role as World Vision's 40 Hour Famine ambassador

Julian Dennison is known for his funny roles in films such Deadpool 2 and Hunt for the Wilderpeople.

But now he's taken on a new, more serious role, helping South Sudanese refugees in Uganda. 

And he's calling on Kiwi kids to do their bit too.

Dennison, 16, has connected with South Sudanese refugees through laughter, but admits learning about the journey these kids have taken to get to Uganda has been tough.

"All of them have come with none of their parents and have come alone by themselves, with no parents and no family... and my heart aches, I feel a lot of pain for them," Dennison told Newshub.

Hundreds of thousands of children have been displaced by the civil war in South Sudan.

Many have fled to refugee camps in Uganda. Dennison visited Bidi Bidi Refugee Settlement in the country's north with World Vision to highlight their plight.

"I've been to these places, I've shot these movies, I've been like around the world but here it's a totally different world," he said.

The Hunt for the Wilderpeople star also taught his new friends a few acting skills.

"The only advice I gave them was to be themselves and to keep pushing, into their passion ...  keep pushing into what they want to do and they will get there... they gave me a lot of advice too though, that you can make something out of nothing."

Dennison is World Vision's new 40 Hour Famine ambassador.

Money raised by children in New Zealand during the 40 Hour Famine, which takes place next week from June 7 - 9, will go towards helping these kids who have so little.

"Raise as much money as you can, get that moolah... it will be a great experience for all youth in New Zealand to get on board and do this... and to work as a country to help another country... to help our neighbours," Dennison told Newshub.

He hopes sharing his stories from Uganda will shine a light on the plight of these kids who have lost everything - except the ability to laugh.

If you want to participate in fundraising for World Vision, click here.