Former Celtic manager Martin O'Neill has refused to rule out a return to the dugout but insists he couldn't take charge of another club in Scotland because of his "wonderful" five-year spell at Parkhead.

The Northern Irishman was appointed as the Hoops boss in 2000 and inherited a squad that finished 21 points behind Rangers in the previous season.

However, O'Neill worked wonders and guided Celtic to a domestic treble during his first season in charge as well as the UEFA Cup final in Seville in 2003 where they came up short against Jose Mourinho's FC Porto side.

Almost every day at Celtic was an experience, as O'Neill told the Dundee Courier: "Celtic are a huge club as are Rangers but look also at a city like Dundee where you have two clubs who both got to a European Cup semi-final in different decades.

“That’s remarkable and you feel a little bit sad that they are no longer at those heights."

O’Neill took charge of Aston Villa and Sunderland after leaving Celtic before spending five years alongside Roy Keane as manager of Republic of Ireland.

A short spell at Forest in 2019 was his last managerial job and the 70-year-old wouldn't rule out a return to management - but it won't be in Scotland.

“I would consider a return to management in future,” he continued. “I loved my time in Scotland – it was a wonderful spell with so many happy memories.

“But I could never see myself managing anyone else in Scotland. After what we had at Celtic I think that would be very difficult.”