Nicky Byrne and Georgina Ahern at the Mansion House

It started on RTÉ's Anonymous when Westlife's Nicky Byrne ambushed his best friend pretending to be a tough talking cop. But the wind-ups are continuing off-camera.

Talking to me at his 30th party in Malahide's Grand Hotel on Friday, Nicky revealed it was best friend Paul Irwin who stuck a For Sale sign on his Malahide home while he holidayed in Portugal last month.

"It was crazy the amount of calls we got from people back in Dublin asking if our house was for sale. Even from other estate agents wanting to sell it for us."

Nicky says he is already planning his revenge.

"An eye for an eye. A tooth for a tooth. He's tried some other stuff which hasn't come off but I have a few tricks up my sleeve. Paul had better watch out," he said.

Nicky attended the bash in Malahide last Friday night along with wife Goergina, in-laws Cecelia Ahern, former taoiseach Bertie Ahern, Miriam Ahern and her partner award-winning restaurateur Terry McCoy.