Teachers unions in Scotland are urging caution over the re-opening of schools.
They have sent a joint letter to education secretary John Swinney saying Scottish schools should not resume teaching until at least August.
Schools in England are set to start reopening next month but the letter attacks what it calls the UK government's "cavalier" attitude.
It also calls for clarity over when Scottish schools will return.
The joint statement would appear to make it impossible for the Scottish government to start reopening schools here before the holidays with the support of the profession.
It reads: "There is a strong argument to maintain a cautionary approach and to reinforce such by indicating schools will reopen after the summer break.
"Not only does that bring clarity to parents, pupils, and teachers, it provides a significant period to plan and prepare for the very real challenge of delivering a blended learning experience for Scotland's pupils in session 2020/21."
It adds a "premature and enforced" return to schools in June would undermine the commitment of staff at a time when they are fearful for their own safety.
The letter concludes: "We would again suggest that indicating an aim for an August restart for schools (subject to all the necessary caveats) would bring enormous benefit in terms of both planning, and securing the active support of staff and parents for an agreed recovery plan focused on the shared aims of equity and excellence and determination to support the well-being of our pupils."
The Scottish government has been asked to comment on the letter however it has always indicated that it was possible schools would not reopen until after the summer holidays.
Grades for qualifications, including Highers and National 5s, will now be based on estimates by teachers and will be awarded by 4 August.
Some councils, including Argyll and Bute, have publicly stated that they are working on the assumption the reopening will happen in August if it is safe.
Schools and councils are also working out what steps they may need to take to deal with the impact of social distancing in the classroom.
This will often mean there will have to be restrictions on the numbers at school at any one time.
It could, for instance, mean some children are in for part of the week only.
The letter also argues there would be little point in schools reopening close to the start of the summer holidays.
It says: "Why would we risk the gains of the lockdown weeks by moving too quickly on schools reopening?
"And for what benefit? Most schools close in June.
"Pulling pupils back for a week or even two is approaching meaningless, especially as many parents will see little value in the exercise and almost certainly keep children at home rather than run a risk to their health."