EIS said members were alarmed and distressed but UsForThem denies the claims.
Chief secretary to the Treasury Steve Barclay turned down a request for borrowing powers for Scotland.
Boris Johnson dismissed calls for indyref2 but Nicola Sturgeon criticised what she called his 'campaign visit' to Scotland.
Boris Johnson will arrive in Scotland on Thursday for the first time since December's general election.
The PM said there has been good co-operation between the four UK nations despite 'surface differences'.
Fire Brigades Union said its members would have had to take on 'significant areas of health and social care work'.