More Welsh students apply to study in England
The number of Welsh students applying to study in England has risen by nearly 20% since 2010, new figures show.
The total staying in Wales has fallen over the same period, data from university admissions body UCAS shows.
Opposition parties are questioning the Welsh government policy of paying most of students' tuition fees, regardless of where in the UK they study.
Welsh ministers said the policy was "the most equitable we've ever had" and Wales was a "net importer" of students.
In 2010 42,150 Welsh teenagers applied to study at English universities, but this year applications reached 50,180, a rise of 19%.
Over the same time, the numbers applying to study in Wales have dropped from 40,560 to 36,700, a fall of 9.5%.
Welsh students pay about £3,500 tuition fees, with the Welsh government paying the rest through a grant.
Angela Milln, Bristol University's director of student admissions, told the BBC's Sunday Politics Wales programme: "Bristol has always been very popular with Welsh students, and I think the Welsh government's approach has meant that students have been able to continue to make their university choices on educational grounds, and not to have to factor in financial incentives or disincentives."
Asked if the university was concerned that the Welsh government might change its policy, she said: "It's a bit early to comment; we don't have any details of what the new policy might be.
"But we will certainly be watching it very carefully; it would, I think, be a great loss to the University of Bristol to see any decline in our Welsh numbers."
Jessica Taylor from Cardiff, a first-year politics student at Bristol, told the programme: "It had less of an impact on my decision [on where to study] because it didn't matter whether it was an English university or a Welsh university that I went to, the fees would have been the same wherever I went, so it took away that aspect - it meant I could choose a university on merit.
"If I had to pay more in the future when I paid back my tuition fees if I came to England, I think I would have considered a Welsh university."
Opposition parties fear the policy of subsidising tuition fees is boosting English universities at the expense of those in Wales.
Welsh Liberal Democrats education spokesman Aled Roberts said: "I think we're starting to see problems with regards to the level of investment in higher education in Wales compared to England.
"Certainly I've been having representations from many of the institutions regarding the quality of living accommodation, the quality of teaching, and this is perhaps a pattern we've seen since devolution where the levels of investment have been lessened in Wales."
The Welsh Conservatives' Shadow Education Minister Angela Burns said: "I do wonder if part of it is the reputational damage we've been suffering in Wales over the past few years in respect of education.
"We had a very undignified fight in the higher education sector conducted by the previous education minister and the education sector ... we have an extraordinary fee-paying policy here in Wales which enables an awful lot of English universities to benefit at the expense of Welsh universities - they are getting the money, Welsh universities aren't."
A Welsh government spokesman said: "Our tuition fee policy, which we believe it the most equitable we've ever had, recognises that the choice of institution and course should be driven by individual circumstances not by the cost of fees.
"Whilst our policy offers freedom of choice for our students, Wales is a great place to study and we would recommend institutions in Wales encourage students to consider the merits of higher education in Wales.
"It's important to remember that the recent WAO (Wales Audit Office) report confirmed that Wales is a net importer of students.
"As such the HE sector in Wales will receive far more income from England than HEFCW pays to English institutions in the form of a tuition fee grant.
"In addition and as a result of the reforms the income to HE will continue to increase for the foreseeable future."