Michael Gove, the Education Secretary in England, has announced plans to axe the body that regulates teachers south of the border, but has not spelt out what arrangements will take its place to check on teachers' fitness for the classroom.
Tony Finn, chief executive of GTCS, has now written directly to Mr Gove, alerting him to the prospect of "significant communication gaps across the UK which may be difficult to address".
Mr Finn has asked to meet officials from the Department for Education in Whitehall "to consider what steps can be taken to ensure that teachers who are guilty of misconduct, deemed incompetent or are listed as unsuitable to work with children cannot easily cross from one jurisdiction to another once GTC England is abolished".
He added: "At present, teachers in Scotland whose conduct, competence or criminal convictions cause them to be removed from our register cannot legally work in mainstream schools in England.
"Similarly, we have recognised protocols which allow us to assess the suitability for employment in Scotland of teachers who have trained or worked elsewhere, including those registered with GTC England."
Mr Gove's department refused to divulge the contents of his reply to Mr Finn, stating this was "not normal practice". But a spokesman did say that officials would be prepared to meet representatives of GTC Scotland to discuss their concerns.