The gap between the proportion of rich and poor teenagers going to a top university is widening, new figures show.
The statistics, published by the Department for Education (DfE), also show that white students and those from a black ethnic background were less likely to go to a leading university than other ethnic groups.
Overall, around 5% of school leavers on free school meals (FSM) - a key measure of poverty - went on to study at a Russell Group university, considered among the best in the country, compared to 12% of their richer peers - a gap of seven percentage points. This is up from a gap of six percentage points in 2010/11.
And around 9% of FSM pupils were studying at one of the top third of universities, compared to 18% of their classmates - a gap of nine percentage points. This is up from a gap of seven percentage points in 2010/11, the data, which is classed as "experimental", shows.
The overall proportion of FSM students who stayed in education after age 18, progressing on to university or vocational training has risen by four percentage points since 2010, according to a DfE analysis, with 66% of youngsters continuing their studies in 2013/14.
Schools Minister Nick Gibb said that this rise is a "vindication of the remorseless focus on helping children from all backgrounds succeed."
According to the Russell Group, of the 14,140 FSM pupils who went to university in 2013/14, 1,820 (12.9%) went to a Russell Group institution.
Sir Peter Lampl, chairman of the Sutton Trust, a social mobility charity, said: "It is very worrying to see the access gap at our most selective universities widen at a time when overall higher education participation has improved for disadvantaged students.
"Today's figures tell us that we need renewed and concerted efforts from government, schools and universities alike to improve participation rates for disadvantaged students at selective universities. We need to see much better co-ordination of access work - and better information for schools - if we are to see significant improvements in the numbers of less advantaged young people going to selective universities."
A breakdown by ethnic background shows that around 11% of white sixth-formers and around 7% of those from a black background went on to a Russell Group in 2013/14, compared to 13% of Asian pupils, 13% of those from a mixed background and 19% of those with other ethic origins.
Around 17% of white pupils and 15% of black students were studying at a top third institution, compared to 22% of Asian teenagers, 20% of those from a mixed background and 28% of those with other ethnic origins.
Research published by Ucas last year suggested that teenagers from ethnic minorities are less likely to get an offer from a top university because they are more likely to apply for the courses and institutions that are the toughest to get in to.
The admissions service looked at offers made by English universities to young English applicants from different ethnic backgrounds and found that although white students were more likely to get an offer from a selective university in general, this is because those with the same predicted A-level grades from Asian, black, mixed or other backgrounds were more likely to apply to the institutions and degree courses that had lower offer rates - effectively the hardest to get in to.
Actual offer rates to students from ethnic minority backgrounds are close to what would be expected, based on their predicted grades and the courses they want to study, Ucas concluded.