Image caption Andreas Schleicher said budget pressure on schools would harm quality

Financial pressure on schools in England will harm standards, one of the most influential figures in world education has warned.

Tighter school budgets mean "you lose and lack in quality", said Andreas Schleicher, boss of the PISA global education rankings.

His comments came amid growing concern among educationalists about school funding shortages in England.

Ministers said it was "incorrect" to say they were making cuts.

"If you take the same system and you take money out of it you lose and lack in quality. I think there's no question around it," Mr Schleicher, told the Times Educational Supplement (TES).

Budget squeeze

In December, the National Audit Office warned that schools in England were facing real terms cuts.

And head teachers have been warning about having to cut school hours, governors have threatened to refuse to sign off budgets and grammar school leaders have said they might have to start charging parents.

Last week, heads were angered when it was revealed that £384m earmarked for converting schools into academies last year had been taken back by the Treasury.

And a government plan to overhaul how school funding is allocated, which is intended to resolve long-standing anomalies in levels of funding, will also risk cuts in most schools, according to teachers' unions.

Mr Schleicher, education director of the Organisation of Economic Co-operation and Development, which runs the PISA rankings, told the TES that in high performing education systems like China, parents and government prioritised spending on education children.

"They invest in the future," he said. "The UK has already spent the money on consumption today, that's where the debt crisis came from.

"It's a value choice of societies to make. Education really is an important choice; that is the future.

"The school system today is your economy tomorrow, and that is something I worry about when governments have an attitude of. 'Oh well, let's cut some corners here'."

Flat results

The latest PISA ranking, published in December, showed the UK lagging behind, having made little progress since the previous set of results, published three years previously.

The rankings, based on tests taken by 15-year-olds in more than 70 countries, showed the UK not only behind top performers such as Singapore and Finland but also trailing Vietnam, Poland and Estonia.

Image copyright NTU Image caption Singapore had the highest achieving schools

England had the strongest results in the UK - but they were described at the time as "flat in a changing world".

At the time, Mr Schleicher raised concerns that teacher shortages were "a major bottleneck" to raising standards.

In response to his latest comments, a Department for Education spokesman said the government had protected core schools' funding "and it is now at a record level - more than £40bn this year".

The spokesman said these figures meant it was "incorrect to say that we are taking money out of the system".

"We recognise, however, that schools are facing cost pressures, which is why we will continue to provide advice and support to help them use their funding in cost effective ways, including improving the way they buy goods and services, so‎ they get the best possible value for their pupils."