The Scottish Government has condemned Celtic's team photoshoot and said it is in breach of the current coronavirus guidance.
The Scottish champions posted a video of behind-the-scenes footage of their team picture session on November 17 on their Instagram and Twitter channels.
It shows the players and coaching team at Lennoxtown in the traditional three rows, side by side with each other.
The Scottish Government has branded the images as "irresponsible", but Celtic say they have not broken any rules.
A Scottish Government spokesperson said: "We would condemn any gathering at a football club or sporting venue that is in breach of the Covid-19 guidance - wherever it takes place - agreed between the SPFL and the Scottish Government, that puts individuals and their families at risk of infection and serious illness.
"If the examples being highlighted today do prove to have happened, we would consider them deeply disappointing and irresponsible, and would expect this to be taken extremely seriously by the football authorities.
"Professional football has considerable privileges - but these depend on following the guidance."
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A Celtic statement said: "The photo was taken and published weeks ago and undertaken with all established protocols.
"We will happily discuss this with the Scottish Government should they wish to do so.
"Celtic's own stringent protocols have ensured that, to date, following thousands of individual tests, we have recorded no positive cases within our squad with the only cases affecting the club being recorded while our players have been away on international duty."
Sky Sports News understands that the SPFL would only become involved if the events affected any fixtures and any probe would have to come from the SFA.
The SFA has been approached for comment.