A leading care home operator has criticised Scottish government plans to relax rules on visiting as "premature" and "ill thought out".
Balhousie Care Group questioned the timing of the move given the rapid increase in the number of Covid cases.
Some campaigners welcomed the decision, which increases the limit on indoor visits from 30 minutes to four hours.
But the first minister stressed the new guidance depends on several factors and is not a "free-for-all".
Under the new measures visitors will also be allowed to hold hands with residents as long as they stick to rules to stop the infection spreading.
Despite the easing, visiting will continue to be "restricted to outdoor and essential visits only" in the Glasgow, West and East Dunbartonshire, East Renfrewshire, Renfrewshire, and North and South Lanarkshire council areas.
But Balhousie Care Group, which has 25 homes across the country, confirmed it will not relax its own visiting rules until there were reassurances of safer and better practices to minimise the risk of transmission of the virus.
Balhousie chairman Tony Banks said: "While we welcome improved and enhanced care home visits, and fully appreciate the wellness benefits more visits would bring our residents, yesterday's announcement was premature and ill thought out.
"Why, in the middle of another sharp spike in community transmissions of Covid-19, would we relax our rules and put our residents and staff at possible risk of infection?"
Almost half of the 4,236 deaths in Scotland where coronavirus has been mentioned on the death certificate occurred in care homes.
'Hell in the Spring'
Mr Banks added: "Scotland's care homes went through hell in the Spring during the first Covid-19 spike. I never want to put our residents, families or staff through that again.
"We need assurances that what happened then will not be repeated.
"Opening our doors wider only widens the risks. And for us, right now, that is an unacceptable risk."
Renaissance Care chairman Robert Kilgour said the changes are "too much, too soon".
Mr Kilgour pledged the group, which operates 15 care homes in Scotland, will endeavour to find a "halfway house" between its current limited indoor visiting and the new guidance.
He told BBC Radio Scotland's Drivetime: "Care homes are not islands. They are part of communities. And if it's rife in communities it will be fighting hard to get in.
"Opening the door to Covid is absolute madness and not something that we would entertain."
Barchester Healthcare chief executive Dr Pete Calveley also expressed concern about the changes.
He told Drivetime: "We are looking after the most vulnerable residents and at a time when everyone else is being stopped from visiting their family or friends in another household we are inviting tens, or even hundreds, of relatives into our care homes untested."
Under the new measures up to six visitors from two households, including children, will be able to attend outdoor visits which can last up to one hour.
Visitors will also be allowed to bring residents gifts and their belongings.
'Not a diktat'
The new guidance also allowed spiritual and faith representatives, hairdressers, pets and therapets to visit care homes again.
The changes will be implemented once care homes are satisfied they can be delivered safely, the Scottish government said.
During her daily media briefing the first minister stressed the new measures were "guidance not a diktat".
Nicola Sturgeon said care homes must be Covid-free for 28 days and have been taking part in weekly testing for all staff to allow these visits.
She added: "It is not an instruction to care homes that they must do this and it is, absolutely, not a free-for-all for care homes, regardless of what the position is."
The first minister added MSPs will be able to consider whether to introduce routine testing for care home visitors when Holyrood returns from the October recess.Ms Sturgeon also said work is continuing to transfer the processing of routine tests of health and social care staff from the UK-wide network to NHS Scotland.
She added there is no issue with capacity but it is being done to "try to shorten the turnaround time for tests".
This follows reports of seven-day waits for staff to receive their test results at care homes where residents have died.
Natasha Hamilton, whose mother has dementia and is in a care home in East Kilbride, welcomed the visiting changes.
But she expressed frustration that they do not apply to the five worst-hit health board areas.
Ms Hamilton told BBC Good Morning Scotland she believes her mother's mental health has deteriorated as she has not had any indoor visitors since March.
She said: "It is hard for us as a family because you are struggling with that guilt as well.
"We wanted to keep mum at home. It wasn't our choice. There wasn't enough help for us to keep her at home. You struggle thinking 'Have we let Mum down?'
"It is the gut-wrenching feeling that mum is so lonely and we can't be with her."
The charity Age Scotland said the changes were "a long time coming".
Brian Sloan, chief executive, said it would be the first time family members could hold the hand of their loved ones in almost seven months.
He added: "It is essential that increased visits to care homes are now available to everyone, wherever possible."