from 5% in 2012 to 4% in 2015, slightly lower than Cambridge’s 6%. The West Midlands secured 6% of Oxbridge places.

London secured 23% of all Cambridge offers and 24% of Oxford’s in 2015, and students in the south-east were awarded 24% of places at Oxford and 22% at Cambridge.

Given the huge regional disparities, Lammy questioned why taxpayers across the country should be expected to contribute to the two universities. “Oxbridge take over £800m a year from the taxpayer, paid for by people in every city, town and village.

“Whole swaths of the country, especially our seaside towns and the ‘left behind’ former industrial heartlands across the north and the Midlands are basically invisible. If Oxbridge can’t improve, then there is no reason why the taxpayer should continue to give them so much money.”

The dearth of offers is particularly severe in Wales. According to the Guardian’s analysis of the new data, just 2% of all offers from Cambridge and 3% from Oxford were made to students in Wales in 2015. Though applications from Wales remain low, Welsh applicants receive disproportionately fewer offers compared with other UK applicants, despite achieving similar GCSE and A-level grades.

Just four students on Anglesey applied to Oxford in 2015, none of whom were successful. Of the total of 29 who applied between 2010 and 2015, just one was successful, in 2010, a 3% success rate.

Figures for Blaenau Gwent are similarly poor. Out of 24 applications over the same five-year period, just two students were successful, one in 2011 and one in 2014. In Merthyr Tydfil, 31 students applied, of whom just two received offers, a 6% offer rate.

In Gwynedd, just five of the 60 students who applied to Oxford were offered places, a slightly higher success rate of 8%, but still far short of the 32% offer rate for students applying from Islington, in north London.

The minister for lifelong learning in Wales, Alun Davies, said: “Significant progress has been made in recent years closing the attainment gap among our pupils, but we recognise that, through working with schools and universities, we need to do more to push our most able students to reach their full potential.”

The Welsh government set up the Seren network in 2015 to identify the highest achieving students in Wales at GCSE in order to work with them through sixth form to support applications to the best universities, including Oxford and Cambridge, as well as top overseas institutions.

Organisers said the scheme was starting to bear fruit, with two students winning places at Yale and one at Harvard this year, but that the full impact of the initiative would not be felt until 2018-19 when students will have received specialist advice and guidance through two full academic years.