Pupils achieved their best A-level results in a generation on Thursday with marks that highlighted the growing gap between the strongest and weakest performing parts of the country.

While the national exam grades were among the highest for decades, regional differences showed areas in the north lagging far behind the south-east. Private schools also continued to outperform state schools.

Students in London and the south-east of England recorded some of the most startling results – more than 30% of their A-level entries were awarded A* or A grades. But those in the East Midlands saw top grades creep up by just 0.2 percentage points to 22.5%.

The West Midlands, which had previously been among the worst performing regions, enjoyed an above-average increase in top grades, but still remained far behind London and the south-east with 24.8% of entries gaining A* or A.

The gap between university application rates from London and the north-east of England, which had the lowest application rate, has also widened further. As a result, while more than half of school leavers in London go on to higher education, only one in three do so from the north-east.

Nick Harrison, chief executive of the Sutton Trust, which campaigns to improve access to higher education, said: “Given the challenges of the past few years, it’s remarkable that more disadvantaged young people are going on to university.

“However, stubbornly wide access gaps remain. The parts of the country which have previously seen fewer pupils go to university are falling even further behind other areas. This gap has increased since last year, and is now higher than a decade ago. Urgent action is needed to tackle this.”

Lee Elliot Major, professor of social mobility at the University of Exeter, said England’s education system remained marred by “stark” regional divides.

“When it comes to A-level results, we effectively have a two-tier system: London and the south-east versus the rest of the country,” Elliot Major said.

“Of course these patterns reflect the differing levels of child poverty across the country but we need to do more to understand the specific obstacles to education in different parts of the country.”

The Department for Education said the growing disparities were a concern that the government aimed to tackle through hiring more teachers and reforming the curriculum taught in state schools.

Bridget Phillipson, the education secretary, said: “I want to thank our wonderful teachers and staff right across the country who have worked tirelessly to support those getting their results under really challenging circumstances.

“This government is committed to breaking down barriers to make sure that all young people, wherever they are from, have the knowledge and skills to seize opportunity.”

But Pepe Di’Iasio, general secretary of the Association of School and College Leaders, said the A-level results revealed “deep inequalities” in society, and warned: “This work will need to produce tangible results sooner rather than later.”

Phillipson also suggested that raising undergraduate tuition fees could deter young people from going to university because of the additional cost.

Asked by Sky News whether tuition fees would be increased within the next five years, Phillipson said: “I do recognise the challenge, and I hear that message from institutions as well, but I think that’s a really unpalatable thing to be considering.

“Not least because I know that lots of students across the country are already facing big challenges around the cost of living, housing costs, lots of students I speak to who are already working lots of jobs, extra hours, in order to pay for their studies.”

In England, 9.3% of A-level entries gained A* grades, while 27.6% got A and A*s. Other than in 2020, 2021 and 2022, when awards were affected by changes to assessments caused by Covid, the proportion was higher than any year since the A* grade was introduced in 2010, and before that going back to 2001.

At the opposite end of the scale, the proportion who failed to reach the lowest grade E increased compared with last year, with 2.5% of entries unclassified.

The rise in top grades meant one in every 11 entries received an A*, with a record 4,135 students celebrating three or more A*s – an increase of nearly 50% compared with 2019, when 2,785 received straight A*s.

The gap in results between grammar schools and secondary moderns – comprehensive schools in selective areas – also widened, with 41% in grammar schools getting A and A* compared with 17% in secondary moderns.

But the results at independent schools trumped even grammar schools, with close to 50% of entries awarded A or better.

Alongside the more than 800,000 A-levels results, more than 400,000 vocational and technical qualifications were also awarded to UK students, including more than 200,000 level three BTecs equivalent to A-levels. Ofqual’s results showed a slight fall in the highest grades awarded for applied general qualifications such as BTecs.

T-levels, which the last government introduced to improve the status of vocational qualifications, showed few signs of succeeding, with more than one in four students dropping out, and a lower pass rate than in 2023 for those who remained. Jacqui Smith, the schools minister, said T-levels “haven’t been developed as effectively as we would have hoped they would have been”.

In Northern Ireland 30.3% of A-level entrants got A or A*, down by seven percentage points compared with 2023, while in Wales the proportion fell from 34% to 27.6%.