The Irish groups are keen to make music together as they want to show solidarity to their native country, with profits from the release going to charity.
The two boy bands - who are both managed by Louis Walsh - performed together for the first time this week in a TV tribute show for late Boyzone member Stephen Gately, and Shane Lynch says it's something they want to continue with.
He said: "I can't believe that it's taken us 12 years to perform together. I'd love to record an album with Westlife and I've told them that.
"It would be nice to do it for charity. American artists like Jay-Z and Rihanna stick together and I think we should be more like that, too."
Ronan said: "I'm so glad that's over. I felt so drained and I don't know how we got through that but I'm glad we did."
Boyzone's new album 'Brother' is out next week.