Threshold 'will destroy careers'
Schools are already advertising for teachers "good enough to cross the threshold", angering unions and provoking fears that teachers' careers could be devastated.
And there are signs that salaries are becoming increasingly negotiable in shortage subjects such as maths and science.
Kemnal technology college, a foundation school in Sidcup, Kent, advertised last week for maths and physics teachers, offering "substantially more than your current salary" to those with the potential to go through the threshold or be fast-tracked.
Headteacher John Atkins said: "I would not want to employ anybody that did not meet those criteria." And for the right candidates, salaries are open to negotiation.
"I would certainy question anyone at the top of the scale who had not gone through the threshold. If they hadn't applied I would want to know what evidence they had that they met the standards. Really, it's the way forward."
Doug McAvoy, general secretary of the National Union of Teachers, warned: "This will have a devastating effect on the careers of some teachers. It's a disturbing pattern - one we predicted."
David Hart, general secretary of the National Association of Head Teachers, warned of a two-tier education system - "a clear result of the market".
"There's nothing wrong with rewarding the best, but if you disadvantage the generality of teachers there's a real danger of low morale and the risk of them simply leaving the profession."
A Department for Education spokesman said it was "perfectly natural for schools to want the best teachers they can get".