Some universities are recruiting students with unconditional offers during the application process, says the university admissions service Ucas.
They are telling students that A-level grade requirements will be dropped completely if they put the university down as their first choice.
It comes as new Ucas figures show one-third of applicants aged 18 received an unconditional offer last year.
Education Secretary Damian Hinds said the proportion was “disturbing”.
He added: “The systematic use of unconditional offers is not in the interest of students and they should not be used just to get people through the door.
“I expect universities to use them responsibly and where institutions cannot justify the rising numbers being offered, I have made clear to the Office for Students that they should use the full range of powers at their disposal to take action.” Read more.