Official figures on staff numbers are "distorted", say unions
The government claims its commitment to recruit 10,000 more teachers by 2006 has been met three years early.
Figures show the number of full-time staff rose by 4,300 between January 2002 and January this year.
Schools minister David Miliband said there were nearly 25,000 more teachers in place than in 1997 and 13,700 more than in January 2001.
But teachers' unions and opposition politicians dispute the findings, which come at a time when some schools are having to lay off staff because of funding shortfalls.
Mr Miliband said: "Rising staff numbers and rising quality are at the heart of an improving education system.
"The figures are the latest result of the government's sustained investment in education since 1997."
The government's figures also reveal the number of teaching vacancies fell by a quarter between January
2002 and January 2003, with the rate now less than 1%.
More than 122,000 teaching assistants are now in schools, almost 16,000 more than last year and twice as many as in 1997.
But Doug McAvoy, general secretary of the National Union of Teachers, said 8,500 of the teachers the government claimed it had recruited since 1997 were "unqualified".
He added: "The figures are distorted. They must be viewed with a very large pinch of salt.
"The question must be, how many of last year's increase are also unqualified?
"It appears that just under 3,000 of the 4,300 increase are either unqualified teachers or overseas teachers, some of whom have qualifications which have yet to be recognised in this country.
"I am deeply concerned by the implication that the government has reached the limit of its ambition for increases in teacher numbers. Schools will not be celebrating if that is the case."
Bob Carstairs, assistant general secretary of the Secondary Heads Association, added: "At a time of redundancies, I'm amazed at what the government is saying.
"A lot of our members will be very surprised to hear that."
Schools around the country are having to make teaching staff redundant over a shortfall in funding, caused by increases to pension and National Insurance payments and changes to working practices.
The government claims local authorities are responsible for the problem, holding back £500m intended for schools.
However, the local authorities say they have not received the money.
The NUT estimates some schools are facing a budget deficit of £200,000.
The Conservatives' education spokesman, Damian Green, said pupil-teacher ratios had risen and there had been a jump of more than 50% in the number of infants in classes more than 30.
"It is clear that in all areas of our schools the crisis is deepening, with one in three teachers leaving the profession after three years."
Phil Willis, the Liberal Democrat education spokesman, said: "The schools minister's claims that the government has met its targets for increasing teacher numbers has all the hallmarks of the disgraced Iraqi information minister.
"If the government hopes to improve standards in our schools by the use of yet more supply, unqualified and overseas teachers, it is sadly mistaken.
"Parents throughout the country will now query whether in the new school year their children will be taught by a qualified teacher or a classroom assistant."
But Mr Miliband said: "Workforce reform is already taking place in many schools and as promised there are more teachers and more support staff - not one at the expense of the other."