By Jesús Aguado, Andres Gonzalez and Amy-Jo Crowley
MADRID/LONDON, July 3 (Reuters) - Santander's SAN.MC plan to buy TSB for 2.65 billion pounds ($3.61 billion) and boost its position in the UK came together only a few weeks ago, after the Spanish bank had been considering a possible exit from Britain, three sources close to the process said.
The lender, grappling with years of underperformance at its UK business and a market share that at best had flatlined, had this year been reviewing its two-decade presence in Britain.
Instead, two developments coincided to hand Santander a chance to snap up TSB, the British unit of Spanish bank Sabadell SABE.MC, one of the sources close to the process said, speaking on the condition of anonymity.
In early May, Santander announced it was selling its Polish bank, raising 6.8 billion euros ($8.02 billion) in the process.
Then word reached it that Sabadell - which itself is the subject of a takeover offer from Santander rival BBVA BBVA.MC - had started receiving offers for TSB, the seventh-biggest British bank by number of branches and a lender that has struggled under Sabadell's control.
Advised by Centerview, Robey Warshaw and Deutsche Bank, Santander and its bankers had worked for the past three weeks to put in an offer late on Friday, the source said.
Sabadell - working with Goldman Sachs and Morgan Stanley - appeared to keep everyone guessing until a Tuesday board meeting.
In the end, Santander beat runner-up Barclays BARC.L, with the difference between the offers tiny, two sources close to the process said.
The deal highlights how rising consolidation in European banking is prompting lenders outside the top tier to realise they need to scale or sell out.
Santander and Sabadell declined to comment.
Centerview, Barclays, Deutsche Bank, Goldman Sachs and Morgan Stanley also declined to comment. Robey Warshaw did not respond to requests for comment.
Acquiring TSB will boost Santander's ranking in UK mortgages to fourth from fifth, RBC estimates. For that, Santander is paying 1.45 times TSB's book value, which analysts said was high but reflected the depth of cost-cutting the Spanish lender believes possible by slashing duplicated back office roles and branches.
"The acquisition of TSB serves to bulk up Santander's UK business significantly and presents material cost extraction opportunities," said John Cronin, banking analyst at SeaPoint Insights.
Cronin said it could be "the first step in a wider play to drive consolidation within the mainstream lending space - with Santander potentially on the offensive".
British lenders flush with cash from higher interest rates are looking at more deals, notably as upstart challenger banks call time on their struggles to take market share from the biggest players.
It mirrors a consolidation process taking place in other European markets, including in Italy, as banks are forced to compete for size because of tighter regulations and massive technology costs.
Bankers say the Santander move will also increase pressure on other British lenders wanting to expand through acquisitions, especially as the number of obvious options declines, with Virgin Money, Tesco's TSCO.L bank and now TSB all taken over in the past 18 months.
NO EASY CUTS
After reports emerged in January that Santander, a sprawling bank operating in 10 core markets, wanted out of Britain, Executive Chair Ana Botin said publicly that the bank was committed to the UK.
While the TSB deal delivers on that promise, the success of the transaction is partly predicated on potentially difficult cost cutting.
Santander has said it expects to take out 400 million pounds of costs, about 55% of TSB's cost base. That well exceeds feasible cost synergies of 40% in the UK based on past transactions, analysts at BofA said in a report.
The bank said the deal will generate a return on invested capital of over 20% and help lift the UK business' return on equity to 16% from an industry-lagging 11%.
Integrating computer systems and migrating customer accounts has proven a tough task in Britain due to a reliance by lenders on often decades-old legacy software. Two of the sources close to the process said Santander would use Gravity, its new IT system, to help with the integration.
The Spanish lender's aim to cut costs by slashing branches and jobs may also trigger protests from unions and customers, as well as political scrutiny.
Santander will also have to battle to win market share from Lloyds Banking Group LLOY.L and NatWest NWG.L that dominate more profitable banking services such as mortgages and credit cards, even with the scale it has added by buying TSB.
($1 = 0.7346 pounds)
($1 = 0.8480 euros)