Union leaders yesterday demanded urgent talks with Royal Bank of Scotland over concern for the group's 100,000 workers and the future of its insurance divisions, following fears that they could be sold off to raise much-needed capital.

The union move came as speculation was rife that Barclays and HBoS would be next in line to appeal to shareholders for funding as banks seek to boost balance sheets. Experts believe RBS's £12bn capital-raising move could open the floodgates for a raft of rights issues.

It has emerged that RBS, which has 17,000 staff in Scotland, is likely to further bolster its financing by selling off its Direct Line and Churchill insurance operations.

Graham Goddard, Unite deputy general secretary, said: "The trading announcement by RBS is a reflection of the challenging environment the financial services sector is facing. Unite has serious concerns about the potential implications for the 100,000 employees of RBS.

"The news that RBS is to review their insurance divisions, Churchill and Direct Line, will cause uncertainty for staff as to their future."

Sir Fred Goodwin later sought to reassure staff. "We have been taking steps to reassure our staff that on selling the business we are not indicating there is anything wrong with it and the sort of people who are stepping up as potential owners would all be appropriate owners and a source of substance and stability for that business.

"It is not going to be sold unless we can attract a very high price for it."