A trustee of the National Union of Students (NUS) has accused the organisation's chief executive of a "fundamental attack" on its staff's right to organise and strike.

NUS Scotland president Gordon Maloney slammed chief executive Ben Kernighan on Tuesday for taking a "belligerent and anti-union" approach to talks over contract changes.

Mr Maloney was replying to an email sent to student union presidents by Mr Kernighan on Monday through a publicly accessible list.