Children in the North are performing worse than their southern colleagues at GCSE level, latest Government figures show.
Provisional data from this year's courses show those in London and the south east of England are out-scoring their counterparts across the country.
Some 66.5% of pupils in the outer London catchment scored A* to C in English and maths, ahead of the likes of the South East (65.5%) and inner London (64.7%).
Only 59.9% of pupils at schools in the West Midlands achieved the same grades - the worst in England, according to the data - below the Yorkshire and the Humber region, which scored 60.4%.
The outer London region also scored well in another attainment measure, with 60.4% of pupils getting 5 A*-C grades, including in maths and English.
The capital and the South East also scored highly, while the West Midlands (54.2%) was bottom of the rankings.
In the East Midlands, 54.4% of pupils achieved five A*-C grades, while the picture was only marginally better in Yorkshire and the Humber (54.9%).
Angela Rayner, Labour's shadow education secretary, described the data as "deeply concerning".
She said: "Many children are performing well and we should celebrate the teachers and schools working tirelessly to help children get good grades.
"However it is deeply concerning that children in the North and the Midlands still appear to be lagging behind their southern peers.
"The difference in geography should not mean a difference in attainment - Government plans for more grammar schools will do absolutely nothing to address this.
"We need to be supporting excellent teaching and leadership in all our schools right across the country to drive up standards, and concentrating on making sure all children are given the opportunity to fulfil their potential, not just a lucky few."
The figures are the first to include the Progress 8 data, the new benchmark based on the progress pupils make from the end of primary school up to their results across eight GCSE subjects.
School Standards Minister Nick Gibb said: "Today's data will help parents identify how well the schools in their local area are performing - ensuring they have the best information available to make that important decision on the right secondary school for their child.
"I am pleased to see that there are more GCSEs being taken in the core academic subjects, those that give students the widest range of opportunities.
"Our focus is on removing unnecessary barriers to creating even more good school places and the introduction of Progress 8 scores will ensure we measure schools on how they support every child to achieve their full potential."