Scotland's national clinical director has said there has to be a "reverse gear" over easing lockdown after 27 Covid-19 cases were linked to a pub.
Prof Jason Leitch was speaking after the cluster emerged on Sunday linked to the Hawthorn Bar in Aberdeen.
NHS Grampian said contact tracing efforts were continuing to find all those associated with the outbreak and 123 people had now been contacted.
The pub said cases were linked to customers who visited on 26 July.
Prof Leitch said appropriate measures were in place at the Hawthorn and that there was "no blame" for staff.
Pubs and restaurants were allowed to reopen in Scotland on 15 July, albeit with physical distancing.
'Protect the population'
The latest cluster follows another outbreak at a pharmacy in Inverclyde last week, which itself was linked to an outbreak at a call centre in Lanarkshire.
It was confirmed on Monday that a further positive case had been linked to the Inverclyde outbreak, bringing the total to 14.
Prof Leitch told BBC Scotland: "I am worried about indoor hospitality. I have been since before and when we made that change.
"I don't think we should overreact, but equally of course we should pay attention to outbreaks in call centres, pharmacies and pubs"
He added: "But there could come a time when we have to go backwards, no question, if we began to see clusters developing or community transmission at a higher level around the country."
He cited the Australian state of Victoria, which has declared a state of disaster and imposed strict new lockdown measures after a spike in cases.
Prof Leitch said health authorities were expecting small clusters around in-door hospitality and that no one thought it was going to be a "smooth journey", but that there was "no risk-free route" out of lockdown.
Figures from the Scottish government on Sunday showed 31 new cases of coronavirus overall in Scotland in a 24-hour period.
That is the highest daily tally for more than eight weeks.
Despite the rise in cases, there were no deaths reported in Scotland due to coronavirus over the same period.