Michael Fassbender and Alicia Vikander love karaoke.

The couple - who have been dating since 2014 and are rumoured to be getting married in Ibiza in the next few weeks - are usually very private about their relationship, but the 40-year-old hunk admitted they enjoy nothing more than group singing sessions when they're not working.

He said: ''We karaoke. It's usually something in falsetto.

''I guess my Frank Sinatra is not bad because I'm kind of a baritone. But if I'm ambitious, I'll try Marvin Gaye or Rihanna.

''Rihanna went really badly - she was there.''

The 'Shame' actor also revealed she and his 29-year-old girlfriend have relocated to Lisbon, Portugal, and are enjoying the relaxed lifestyle so much, they can see it being their permanent base.

He told Grazia magazine: ''At the moment we live in Lisbon. I like it, I like the people and the fact it's right next to the ocean.

''The weather, the food, the wine is always good. We have a UK base, but Lisbon is becoming home.''

The Hollywood duo have been tight-lipped about their romance ever since they met on the set of the Derek Cianfrance-directed drama 'The Light Between Oceans' three years ago.

Despite this, Michael revealed in an interview last year that their relationship ''just happened''.

He shared: ''It just happened. It's good that it happened. It is what it is.''

Meanwhile, Alicia recently revealed she has ''always wanted'' to have children.

She explained: ''I don't even have children, and it's the wonder of my world. I've always wanted kids. I've never been pregnant, but I hope to have a family one day.

''It's both the expectation and knowing that it should be the greatest experience of my life - and suddenly from one day to another, it's a reality; it's a new chapter of your life.''