The "five nations" talks were a centre-piece of discussions at the first international conference of teaching councils, hosted by the GTC in Edinburgh this week.
But Matthew MacIver, the council's registrar, admitted it would be "very difficult and we are only at the start of the journey". There were certain standards the GTC would not compromise, such as an all-graduate profession.
Peter Peacock, Education Minister, told the conference that, as teacher mobility grew, it was much more important to strengthen mutual recognition systems.
Mr MacIver said that mutual recognition should include issues such as professional misconduct, child protection and professional standards.