Two separate errors in spreadsheets at Leeds University came to light when the institution was left with "significantly" less than it had expected.

The mistakes were also carried forward in financial forecasts over a five-year planning period up to 2013, meaning a miscalculation of around £100m.

Bosses at Leeds University insisted last night that the mistakes were not responsible for the institution now looking to making savings of £35m because of cuts in higher education funding.

A spokesman said: "The two are not connected. The £20m forecasting error is irrelevant to the economies exercise because it isn't money we ever had – it's just a spreadsheet error.

"Like other universities, we are looking ahead in our financial planning to help us remain in control of our destiny and finances.

"As our staff understand, we have to make savings because we know our budgets will be affected by public sector cuts. We are also being affected by the recession and face other cost pressures including pensions."

A statement on the university's website adds: "Had the forecasting error not occurred, it's likely we would have embarked on the economies exercise some months ago."

In a speech to the university's senate last month Vice Chancellor Professor Michael Arthur said the accounting errors related to research and expenditure on bursaries.

He also said they were made before the current head of management accounting, Angela Byram, or the director of finance, Jane Madeley, were in post.

But the University and College Union's Leeds branch vice president, Gavin Reid, said: "We have been told that Leeds University realised they have less of a cushion than they previously thought so of course it is linked to the cuts."

Prof Arthur told staff there were no plans in place for compulsory redundancies in a live webcast on the university's website yesterday.

He said the university aimed to achieve savings through voluntary means.

Answering questions which had been submitted by staff, Prof Arthur said cuts in higher education funding were expected regardless of the outcome of next year's general election.

He also warned that universities could face "in year cuts" if a new Conservative government held an emergency budget after taking office.

The University and College Union have voiced fears that up to 700 jobs could be lost at Leeds University if 60 per cent of the savings it makes are in staff spending.