Vice-chancellors have told the Education Minister, Julia Gillard, in private meetings that a target of teaching an extra 330,000 students by 2020 would require thousands more academics and a multibillion-dollar building program.

In her review of higher education, Professor Denise Bradley highlighted the ageing academic workforce, increasing casualisation of teaching and research, and declining working conditions and standards as significant issues.

Until now Australia has gone overseas for academic staff - in 2006, 40.5 per cent of academic staff were born outside Australia - but that source is drying up because of global competition.

On the eve of the Government's response to the Bradley review, Ms Gillard said the academic shortage was a big challenge and the Government needed to work with universities to make an academic career more appealing.

"One of the main issues raised is how we would generate an enlarged higher education workforce if the nation was to embrace ambitious [student number] targets," she said. "I think the workforce reality in higher education would be considerable even before you consider questions of growth in enrolment.

"The baby boomer demographic bulge is showing, and the underfunding of recent years has made it it very difficult for universities to offer a secure career path through for young people."

Professor Bradley's review, released in December, calls for fairer access for poorer, rural and regional students to higher education.

She recommends a $7 billion expansion of higher education and research, boosting the proportion of 25 to 34-year-olds with at least a bachelor's degree from 29 per cent to 40 per cent by 2020, and a new funding mechanism based on student vouchers or "learning entitlements".

Critics, including members of the elite Group of Eight universities, have described the report as a "road map to mediocrity", lacking vision and failing to provide a blueprint for the future.

Ms Gillard said Professor Bradley had displayed a "strength of vision" with her review. "People are more pointed in the media than they are in the meetings," she said. "The review would be appreciated if properly read and considered."

Ms Gillard began a series of six discussions three weeks ago so that universities and the vocational education and training sector could respond.

The vice-chancellor of the University of Western Sydney, Professor Janice Reid, said the Government had to make an academic career more attractive for Australian and overseas students aged in their 20s or 30s.

She said the sector was aware of the challenges of a shortage of senior academics. More financial support had to be given to students with doctoral scholarships as well as making the work environment more attractive by improving staff-student ratios.

The vice-chancellor of the University of Technology Sydney, Professor Ross Milbourne, said the Government should reduce the target of 25 to 35-year-olds with a degree by 2020 to 35 per cent as a more manageable target. He said the issue of attracting quality academic staff was a global one and not peculiar to Sydney.

"It is vital that Australia ensure it maintains a world-class education system so universities can attract the best academics and students who can in turn become academics."