Glasgow has an "uncomfortably high" amount of COVID cases and will remain in level three of Scotland's restrictions, Nicola Sturgeon has said.
Giving a coronavirus briefing, the first minister said she had hoped to ease the strictest curbs in the city this week but advisers felt the move would be "premature".
But she added Glasgow could move down to level two from next Saturday, with a decision due on Wednesday, amid signs COVID-19 measures are having an impact.
It comes as the Johnson & Johnson single-dose coronavirus vaccine was approved for use in the UK, by the medicines regulator.
Ms Sturgeon also revealed that Scotland's R number could be as high as 1.3, which indicates the infection is spreading at an increasing rate, with the Indian variant now accounting for more than half of the country's COVID cases.
As such, there still needs to be a "reasonable degree of caution" exercised with Friday's daily case number - 234 - the highest since 25 March.
She added: "The increase in cases so far does seem to be concentrated in younger age groups and this may indicate that vaccination is having a protective effect for older people which of course we want to see."
Cases last week in Glasgow continued to rise by 30%, the first minister reported, but public health experts have said the restrictions have had an impact on transmission in the city.
Ms Sturgeon said: "There are some early signs that the situation is stabilising in Glasgow.
"Weighing up all of these different factors is inevitably really difficult - case numbers in Glasgow… are uncomfortably high, but we are seeing signs of progress.
"The view of the national incident management team is two-fold.
"Firstly, that it would be premature to move Glasgow out of level three immediately this week while the situation remains so fragile.
"However, and secondly, if incidence continues to stabilise and assuming levels of hospitalisation remain reasonably stable, the incident management team has made clear to me that they would support a move to level two from the end of next week."
Seeking to reassure the public, Ms Sturgeon added: "My message to the people of Glasgow is don't lose heart, on the contrary, take heart from the progress that we are seeing.
"I live in Glasgow, so I know how hard this is from my own personal life, but please continue to help with all of the public health efforts that are in place because if we continue to do this then we will make that move down from level three to level two and then after that hopefully get back on track and down the levels further."
Ms Sturgeon also said she would confirm if the rest of Scotland would be able to move to level one on 7 June, as planned, next week.
In the meantime, she urged the public to do their "civic public duty" and get vaccinated.
Ms Sturgeon said: "Getting vaccinated is in all of our best interests, whatever age we are.
"It's also the most important thing we can all do to help our family, our friends and our neighbours - by getting vaccinated we're helping reduce the overall harm and making it easier for all of us to get back to normal.
"Rolling up our sleeves - not once but twice - really is part of our civic public duty to each other and to the country right now."