Britain's biggest union is pressing Northern Rock to pledge that no job cuts will be forced on its staff after the nationalised bank yesterday began talks on plans to cut its workforce by nearly a third.

Unite wants Northern Rock to commit to no compulsory redundancies as the bank prepares to speed up the programme of job cuts. Originally it had said that it wanted to cut 2,000 jobs by 2011. But yesterday the bank said that it expected that the majority of the cuts, which will occur across all staff grades, would go through by the end of this year.

Graham Goddard, deputy general secretary at Unite, said: “If downsizing goes ahead, Unite will be demanding that Northern Rock gives a commitment to no compulsory redundancies. The workforce did not contribute to the situation in which the bank now finds itself and should not be expected to pay the ultimate price by being forced out of their jobs.”

Unite is also seeking assurances on pensions and long-term job security for the remaining staff. It also gave a warning that it would oppose a “piecemeal” sale of the bank's assets.

The job cuts are part of the bank's attempts to cut costs, improve profitability and return to commercial ownership. The bank is intending to pay back a £25 billion emergency loan that the Bank of England supplied last September when Northern Rock issued a profit warning that led to a run on the lender. The new management of the bank is hoping to repay the loan over the next three to four years.

Northern Rock is working on halving its £110 billion mortgage book and will focus on low-risk mortgage lending. It is also aiming to build up its savings business.

Ron Sandler, executive chairman of Northern Rock, said: “In order to meet our corporate objectives, it is necessary for us to contract to a smaller and more sustainable business. Regrettably, this is likely to involve a reduction in staffing levels of about 2,000 and a restructuring of the company.

“This is a very difficult time for our people and we will continue to work closely with them and Unite, to minimise the extent and impact of potential job losses. We remain closely engaged with local agencies, including One NorthEast [the regional development agency], to ensure that those who may be affected are offered as much support as possible.”

Northern Rock said: “The company will now commence the formal 90-day consultation period with Unite and other employee representatives. The likely start date for any potential job losses has not been set but will be agreed, with Unite and other employee representatives, during the course of the consultation period.”

Local authorities and business groups in the North East have formed the Northern Rock Response Group to help those who lose their jobs to find new employment. Unions and local organisations are concerned that sudden large-scale job cuts will have a strong effect on the local economy.

Controversy over the cuts could prove politically damaging for the Government as most will fall in Labour heartlands in the North East. The Government was criticised for not acting more quickly when Northern Rock plunged into financial trouble seven months ago. But Alistair Darling, the Chancellor, has said that the taxpayer will benefit when the bank is sold off again.

The bank ignited further controversy in March when it was revealed that Adam Applegarth, its former chief executive, received a £760,000 payoff.

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