Chancellor Gordon Brown has promised to try to persuade rebel Labour MPs that proposed school reforms for England are vital for the success of the economy.
The Chancellor called for a "world class education system"
"No country in the modern world can be first in business if it is second in education," he told the Sun newspaper.
Tony Blair has said getting the plans giving schools more freedom through Parliament would be a "highwire act".
More than 90 backbenchers have voiced opposition to the reforms, seen as central to Mr Blair's authority.
Mr Brown told the Sun he and the prime minister were working on the reforms together.
"I cannot be stronger about the importance I attach to this reform programme and the link between education and the economy," he said.
"As Chancellor I know the next stage of our economy depends on the highest standards of education in our schools, colleges and university."
He said it was his job as Chancellor to persuade people of the importance of the education reforms and that he wanted every school to be a good one.
Mr Brown said he would be explaining to the rebel MPs the importance of education to the economy over the next few weeks.
"I will explain to them our ambition is to have a world class education system and the importance of what we are trying to do," he said.
He said for too long in the UK there had been "a culture of second best" and a "poverty of aspiration".
BBC political correspondent Carole Walker said Mr Brown's intervention provided "critical support" for the prime minister and might well reduce the scale of any rebellion.
Under the plans, Mr Blair has said schools would not be forced to become trusts, but would have "permission" to do so.
He said selection by ability was "not a sensible way forward" and it was wrong to divide children up into successes and failures at the age of 11.
Tory leader David Cameron has offered to support the government's plans.
The Education Bill, based on the white paper, is due before MPs in February.