HSBC recently approved a £12.5bn share sale
Europe's biggest bank, HSBC, has said up to 1,200 of its staff in the UK could face redundancy.
The bank said the individuals who could be affected by job losses were being briefed on Wednesday.
At least a third of the staff cuts will come from back office operations such as call centres, not from High Street branches, a spokesman said.
Unions are disputing the figure, saying the total number of jobs lost in the UK will be closer to 3,000.
An operation centre in Leamington Spa, near Warwick, will lose 280 positions, about 150 jobs will be lost in London and and a call centre in Newport, south Wales, will be shut down, HSBC spokesman Tim Pie said.
The jobs cuts announced are in addition to the 500 jobs lost at HSBC's London head office in December.
"The operating environment for banks in the UK is extremely challenging and will remain so for some time," HSBC UK managing director Paul Thurston said in the statement.
"There are difficult decisions that have to be made as we adapt to a new environment," Mr Thurston said.
Commenting on the closure of the call centre in Newport, which employs 90 staff, South Wales assembly member Mike German said he was "dismayed" at the announcement, saying it was a "complete turnabout" nine months after an announcement to create 150 new jobs there.
"HSBC's investment of £14m in Newport is in danger and I will be asking the Welsh Assembly Government to pull out all the stops, save local jobs, and secure that investment that was due to be made this year and in 2010," he said.
The company's chief executive in Wales, Alan Jarman, said the "very regrettable" decision was taken in a "rapidly changing economic environment".
A union representing some HSBC staff responded angrily.
"Unite can see no justification for the efficient and dedicated staff in the UK to lose their jobs and all basic and standard current accounts to be serviced from India," said Derek Simpson, the joint general secretary of the Unite union.
"This is a kick in the teeth of the bank's employees."
Unite argues that the total number of job losses will be 2,900 as roles are left unfilled when employees are moved into different areas, retire or resign.
Mr Pie said those additional job losses through attrition had been discussed with the union, but no number had been decided by the bank.
HSBC has a total staff of about 330,000, with 58,000 of those employed in the UK.
Unlike other UK banks, HSBC has not received any support from taxpayers. But last week shareholders approved a £12.5bn share sale - the biggest in UK corporate history.
Financial firms have been cutting workers and trying to raise money as they struggle to cope with the worst crisis since the Great Depression in the 1930s.
The Royal Bank of Scotland, which is one of several banks that have been bailed out by the UK government in exchange for stakes, has said it will cut 2,700 jobs in the UK.
In January, Barclays cut 4,200 jobs from its UK banking business, with half coming from back office operations and the other half coming from its fund management, private banking and investment banking units.
Insurers Royal Sun Alliance and Standard Life have all said they will cut jobs.
In a further sign of the difficulties facing the sector, Legal & General said it will cut 650 jobs, including the 450 announced in February.