Fears over the future of hundreds of banking jobs in Oxfordshire are growing after HBOS and Lloyds TSB raised the cost-cutting target of their proposed merger to £1.5bn.

Neither of the banks could give any assurances to staff as the financial implications of the Government-backed merger started to unravel.

About 300 staff are thought to work for the banks in the county and with Lloyds and HBOS branches currently operating independently in high streets, it is thought branches could close to remove duplication and cut overheads.

There are 24 branches of HBOS and Lloyds TSB in the county.

HBOS spokesman Andy Maciver said: “There is no further detail on branches or job numbers and we don’t know when that sort of information will be available.

“Executives are making sure the deal goes through and decisions will be made after that.”

Lloyds TSB spokesman Emile Abu-Shakra added: “This is being revealed stage by stage over a period of weeks and months and the detail is yet to be announced.”

The uncertainties over job cuts came after Lloyds TSB said it now hoped to find an extra £500m from the combined cost base after its takeover of HBOS.

Both banks confirmed their commitment to the deal, despite speculation of potential rival bids from mystery suitors waiting in the wings.

In trading statements also released by both banks, HBOS revealed a further £2.72bn hit from the credit crunch, while Lloyds said it had seen a "substantial reduction" in profits since the start of the year.

Lloyds is hoping to deliver annual cost savings of more than £1.5bn by the end of 2011, compared with its previous estimate that it would be able to save around £1bn or 10 per cent of the combined group's cost base.

The acquisition will change the face of high streets, particularly in market towns like Witney and Abingdon, which will each have three branches of the new proposed combined banking giant.

Bicester, which has Halifax and Lloyds branches in Sheep Street, could also be affected.