The Vice Chancellor of Sussex University insisted last night that the loss of its internationally-renowned chemistry department was not a done deal.

Professor Alasdair Smith told a hostile committee of MPs that he was "desperately keen" to retain the department in some form.

But he also admitted that it was difficult to allocate resources to a department which attracted only 20 students a year while English recruited 300.

Hauled before the Science and Technology Committee to explain the university's plans, Prof Smith said the retention of the chemistry department was still an option. But this was only viable if chemistry was returned to the "absolutely first grade department" it was before a series of high-calibre departures.

The alternatives were either closure or an "intermediary" option in which chemistry would be "refocused" to concentrate on the subject's relationship with other sciences.

Prof Smith said: "It's very, very difficult to justify the kind of investment that would be required to restore the department to the position it was in six or seven years ago on the back of the kind of student recruitment we have had over the last few years."

His proposal, for a chemical biology department, has been dropped. The alternatives are being considered by the university's senate.

Prof Smith added: "The closure option I didn't put forward because I'm very strongly committed to science at Sussex."

Dr Gerry Lawless, the university's head of chemistry who has resisted the moves, said he had repeatedly asked for vacated positions to be filled. Sitting beside Prof Smith before the committee, he added: "This is not a department that's under-performing, it's a department that's under-resourced."

Brighton Kemp Town MP Des Turner, a member of the committee who was instrumental in last night's hearing, warned Prof Smith that, should the department survive the current review, its reputation might not now recover.

Chairman Phil Willis said: "To be taken seriously as a science university without a chemistry department is laughable."