Former Celtic striker Walker, speaking in his role as a pundit for Sky Sports, criticised the club for "dismal governance" over the trip, which he labelled "a jolly".

Ahead of the trip to Livingston on Wednesday night, an angry Lennon, who confirmed that one Celtic player who had been self-isolating had tested positive for Covid-19 on Monday, turned on Walker.

He said: "You can't go on a public platform and spread lies and insults about my professionalism, my players' professionalism.

"About 70-80 per cent of the group are teetotal and you know the inference and innuendo that he is making. It is not a stag do, it isn't an '18-30′ even though it has been portrayed like that.

"We went out there with the best intentions.

"I want Andy to apologise because he was demanding apologies from the club.

"I want an apology from Andy because he has questioned my professional integrity, my players' professional integrity and the use of the word jolly is crass and arrogant.

"He accused the club of being arrogant last week. We weren't.

"Does he speak for the Celtic support? Is he all of a sudden the man of the people?

"Andy's been in the game here for 20,30 years, he has made no contribution to Celtic whatsoever.

"He stood up there as if he is a Celtic legend and a stalwart of the club, putting the boot into me, the club and everybody else. He is totally out of order."

Sky declined to comment when contacted by the PA news agency.