Last checked at 
* Bostock takes up position with immediate effect
* Ana Botin will stay on board as non-executive
* Chairman says Bostock will bring continuity
* Santander UK expected to float in next 2 years (Adds further details, background)
By Matt Scuffham
LONDON, Sept 29 (Reuters) - The British arm of Spanish bankSantander has appointed Nathan Bostock as chief executive,handing the former Royal Bank of Scotland financedirector the task of overseeing a planned London listing.
Bostock, 53, succeeds Ana Botin, who was appointedchairwoman of Madrid-based Santander Group followingthe death of her father Emilio Botin earlier this month. Bostocktakes the UK CEO role with immediate effect.
Bostock was appointed deputy chief executive of Santander UKlast December with a view to being Ana Botin's successor, buttook up the job only last month after serving a lengthy noticeperiod at RBS.
Botin, who will stay on the Santander UK board as anon-executive director, had been expected to oversee an initialpublic offering (IPO) of Santander UK shares in London in thenext two years before handing over to Bostock.
Santander UK, the biggest contributor to Santander's overallprofit in the first half of 2014, is one of a number of Britishbanks considering an IPO.
Banks are responding to demand from investors who see UKretail banking stocks as offering exposure to Britain's economicrecovery and expect banks to benefit from improved margins wheninterest rates rise.
Lloyds on Friday sold a further 11.5 percent stake in TSB which it spun off earlier in the year, in a shareplacing that was covered several times over and attractedinvestors from the United States as well as Europe.
Virgin Money is expected to announce itsintention to float within days and challenger bank Aldermore ismeeting investors ahead of a listing next month. OneSavings Bank listed in London earlier this year.
A LIFE IN BANKING
Bostock has been employed at RBS or Santander for much ofhis working life, but has switched roles several times. Hejoined RBS in 1992, before departing for Abbey National, whichwas later bought by Santander, in 2001. In 2009, he leftSantander to rejoin RBS as head of restructuring and risk.
Bostock didn't take up the role of Botin's deputy untilAugust because RBS bosses, stunned by his decision to quit asfinance director after just ten weeks in that role, forced himto serve out a long period of notice.
Despite that, Santander's board has decided he is ready tobecome chief executive and the appointment prevents its UKbusiness facing a prolonged period of boardroom upheaval. Thebank is also searching for a successor to Chairman Terry Burnswho is due to retire at the end of the year.
Burns said Bostock's appointment would enable a "continuityof vision and strategy".
"He brings a strong understanding not just of Santander UK,having worked for us as an executive director up until 2009, butalso of the wider UK banking industry, regulatory environmentand economic climate," Burns said.
Santander UK reported a pretax profit of 545 million pounds($885 million) in the first half of 2014. The bank has benefitedfrom an improved margin and from attracting more customers toits 123 account, which offers a higher-than-usual interest rateon balances up to 20,000 pounds and cashback on utility bills.
It has been one of the main beneficiaries of new rules thatmake it easier for customers to switch banks.(1 US dollar = 0.6159 British pound) (Editing by Keith Weir)
