FORMER Royal Bank of Scotland finance director Nathan Bostock has been put in charge of operations and strategy at Santander UK and appears to be favourite to be its new chief executive.

Mr Bostock only joined Santander last month as its deputy chief executive.

Prior to that he had been serving out his notice period at RBS having handed in his resignation just 10 weeks after taking the finance director post in October last year. He stepped down from the RBS board at the end of May.

Before his most recent spell at RBS, which began in 2009 in the aftermath of its taxpayer funded bailout, Mr Bostock worked in several positions at Santander including chief financial officer.

The highly-respected Ana Botin has already moved from chief executive of Santander UK to be executive chairman of the wider Banco Santander group following the recent death of her father Emilio.

Santander UK chairman Terry Burns is also expected to retire before the end of this year.

The boardroom upheaval is likely to have further delayed the long-mooted stock market flotation of Santander UK which had been expected to finally come to fruition over the next 18 months.

Santander UK's board met yesterday but stopped short of formally naming Mr Bostock as its new chief executive.

However the 53-year-old is widely seen as the favourite to land the job. His appointment to the post would need to be cleared by watchdogs at the Prudential Regulation Authority and the Financial Conduct Authority.

Mr Bostock was replaced at RBS by Ewen Stevenson.

Towards the end of 2011, Mr Bostock had planned to leave RBS to join Lloyds Banking Group, but later reversed that decision.

At that point he was running risk and restructuring for RBS. He replaced Bruce van Saun as finance director when Mr van Saun returned to the United States to run Citizens Bank.

Santander's UK operations include the former building societies of the Abbey National, Alliance & Leicester and Bradford & Bingley. In the first six months of this year pre-tax profits increased 18 per cent to £545 million.

Commercial lending was said to have grown 10 per cent while the mortgage book was up by £4.9 billion, to £12.8bn, year-on-year.

In the UK Santander has around 14 million customers and more than 980 branches. It employs in excess of 20,000 people.

Banco Santander yesterday sealed a deal to buy Canadian auto financing specialist Carfinco for around £167m.