RBS has admitted to mis-selling taxpayer-backed loans to small business, according to The Times. "An internal investigation at the lender has revealed serious failings in the way in which it used the Enterprise Finance Guarantee, a government scheme designed to boost lending to smaller companies," the paper said.The Telegraph says that Samsung has approached smartphone maker BlackBerry about a possible takeover worth $7.5bn, causing shares in the Canadian group to soar on Wednesday. The rumours, first cited by Reuters, suggest Samsung proposed an offer of $13.35-15.49 a share, a 38-60% premium on BlackBerry's current share price, at a meeting last week.Oil industry consultancy Wood Mackenzie has warned that oilfields in the North Sea could be shut down if the oil prices falls any further, writes The Guardian. The collapse in Brent, currently at around $46 a barrel, means that some UK production is already failing to break even, it said.German bank Deutsche Bank is looking at the possible sale of its retail banking operations, reports the Financial Times.Mark Carney, the Bank of England governor, has said that the falling oil price represents a "negative shock" for Scotland, but the impact is "substantially mitigated" by its position within the UK, writes The Telegraph.Jamie Dimon, the head of JPMorgan Chase & Co, accused regulators of an "un-American" attack on the bank after it reported falling profits in the fourth quarter and a $1bn bill from legal expenses due to investigations into alleged misconduct, The Times writes. He said: "Banks are under assault [...] We have five or six regulators coming at us on every issue. Obviously companies make mistakes. We try to resolve it [...] we admit it."