Adrian Dunbar on home, Irish unity and his new Line of Duty catchphrase

From the abattoir to AC-12. One of Northern Ireland's best known and most successful actors, Adrian Dunbar, is fiercely proud of his Ulster roots which he said have shaped his life, his career and his politics.

Even his most famous role - Supt Ted Hastings who runs the fictional anti-corruption unit AC-12 in the BBC drama Line of Duty - owes much to his Fermanagh heritage.

When times got tough in his career he reminded himself of when he had made ends meet heaving bags of salt in freezing temperatures in an Enniskillen abattoir.

But that was all a long time ago. Fresh from filming the much-anticipated seventh series of the hit TV show that's made him a household name, he agreed to talk politics.

Speaking to Dunbar at Belfast's Lyric Theatre, it is clear the huge warmth he retains for home, despite having lived in England all his adult life.

"Growing up in Enniskillen in the 1960s, politics didn't really feature in our house," he told the BBC's Red Lines podcast.

That is perhaps surprising for a man who now holds such clear views on so many issues of the day, from Brexit - responsible, in his view, for "stoking the fires of English nationalism" - to future constitutional change on the island of Ireland, which he maintains is already "on the road to happening".

There is one subject he does recall being discussed around the Dunbar kitchen table in his youth, however, and it was an issue that was central to the politics of the time - housing.

"It's really interesting to me today to see that housing is still central to so many of society's ills - the need for housing and people's need to have a house and feel secure," he said.

He puts a lot of that down to his mother who was, he said, "always very straight about everything. She was very fair and she taught us to be fair".

His early years in Enniskillen were "halcyon days", fishing in the lakes in summer.

But in his mid-teens his parents moved the family to Portadown. He remembers "difficult, scary times" as sectarian tensions simmered in the town and he was relieved when the decision was made to move back to Fermanagh after several years.

Dunbar is convinced that his growing interest in music and drama kept him out of trouble.

It offered him a safe, neutral space to meet people from all kinds of backgrounds and pursue his love for acting.

In 1980, in his early 20s, he secured a place at the prestigious Guildhall School of Music and Drama in London. He has lived in the city ever since.

You might imagine that almost five decades of living in Britain could have affected his sense of who he is, but not so.

"I'm very proud, having watched British television all my life, that I've created an iconic character on British television," he said.

"For me that's just the best thing ever. However I'm Irish, I've always been Irish... all my obsessions are Irish. I have a house in Ireland, I'm here in Belfast all the time. I've hardly left the place since I went to London."

Even though his career has seen him build a successful career on British TV and film and on the stage with the likes of the English Theatre Company, the Royal Shakespeare Company and the National Theatre, he is clear about the importance of his roots.

That may well be why he does not shy away from the big constitutional debate here, conceding he is an unapologetic supporter of change.

"Partition has never worked anywhere it's been tried across the world. It's certainly not working here," he said.

"We need change. It's going to be gradual... Most of the people are engaged with the conversation already."

As for the timing of any future border poll, he is in no rush to see it happening any time soon.

"A referendum doesn't really bother me. It's going to happen. What's more important is to lay the ground and have us all going into a referendum knowing what's either side of the debate and what the upsides and the downsides are."

As part of a broadly "non-aligned left", would he seek to play a part in any public debate about constitutional change?

"No, because actors for the most part have to be above party politics and at the moment it's all about party politics here - and will continue to be for some time," he said.

"I don't think that I'd actively engage in it other than just endorsing the fact that I think the island needs to be united."

Still, it is an issue Dunbar has clearly thought about and is enthusiastic about, and you could well imagine how campaigners for change would be keen to persuade him to play a big part in that conversation.

Whether that happens or not, we will see.

In the meantime, always conscious of those Irish roots, Dunbar promises an ever-expanding treasure trove of scene-stealing Ulsterisms from his character, Ted Hastings, in the next series of Line of Duty.

Expect "Mother of God" and "Jesus, Mary and Joseph and the wee donkey" to be joined by the straight-faced superintendent's latest one-liner: "Don't stall the digger".

You heard it here first. No doubt the T-shirt and the mug will be along shortly.

The full interview with Adrian Dunbar is available as a Red Lines podcast on BBC Sounds.