Long-serving Dunne culled my Millwall
Millwall captain Alan Dunne is looking for a new club after being one of 18 players released by the Lions following their relegation from the Championship.
Dublin-born defender Dunne (32) grew up in London and joined the Millwall academy as a 10-year-old. Lions chairman John Berylson said: "It is always sad when a member of your family who has lived with you for a long time leaves home.
"While Alan will continue his playing career elsewhere, it would not surprise me to see him back here in some capacity further down the line."
Irish trio David Forde, Aiden O'Brien and Shaun Williams remain under contract at The Den.
Harris expects some interest in Forde due to his international ambitions, although the Galwegian signed a good contract last summer to commit his future to the club amid interest from Celtic, Crystal Palace and Fulham. Williams is also well regarded.
Elsewhere, Wolves have decided to retain Irish U-21 striker Liam McAlinden for another season after exercising an option on his contract.