Business week in pictures

Tesco blamed a disappointing Christmas performance on the snow. Shares in UK's biggest retailer fell sharply after it blamed a poor performance at its vast non-food business on the weather, which it said prevented shoppers from reaching its out-of-town stores. Analysts believe the icy conditions cost Tesco around £50m in lost sales. Photograph: Glenn Copus/Evening Standard/Rex Features

A slew of major high street chains reported sharp sales falls over the crucial festive trading period. The toll of the snow on retailers' sales was underlined as the Co-operative Group, Dixons Retail, Halfords, Thorntons, Game Group and New Look all issued downbeat trading statements Photograph: Dan Kitwood/Getty Images

But Sainsbury's enjoyed its Christmas. It leapfrogged Asda to become the country's second-largest supermarket in December as new stores and strong Christmas sales helped it recapture a ranking it last held in 2003. Chief executive Justin King said supermarkets had benefited from a 'following wind' over Christmas as customers opted for the convenience of 'one stop shopping', buying gifts such as clothing and DVDs along with their groceries. Above, a Sainsbury's employee moves Roses chocolates across the warehouse floor at Sainsbury's Waltham Point depot Photograph: Dan Kitwood/Getty Images

Marks & Spencer also produced better than expected Christmas sales despite taking a £50m hit from the snow. Chief executive Marc Bolland said the severe weather had made for a challenging first Christmas at the helm but the stores had 'traded well' as 'customers continued to return to M&S quality'. Above, the celebrity line-up in the Marks & Spencer Christmas marketing campaign Photograph: M&S/Rex Features

Bob Diamond, the new boss of Barclays, stood firm against demands by MPs that he forgo his 2010 bonus as he said the time for apologies from banks was over. In his first and at times fractious appearance before the Treasury select committee of MPs, Diamond also said that banks should be allowed to fail and should not be bailed out by the taxpayer Photograph: Ben Stansall/AFP/Getty Images

The Liberal Democrat business secretary, Vince Cable, and the Treasury's chief secretary, Danny Alexander, stepped into the bankers' bonuses row, saying banks will have to show restraint, as David Cameron promised he would deliver a deal that included lower bonuses, higher lending and higher taxes. Lord Oakeshott, a Lib Dem Treasury spokesman, also insisted his party had not given up the fight with the banks, and negotiations were continuing Photograph: Dan Kitwood/Getty Images

Employers will no longer be able to force staff to retire at 65 from October, the government announced. Ed Davey, the employment relations minister, said the phasing out of the default retirement age was 'great news' for older people, business, and the economy. He also claimed that far from hurting the chances of young people getting jobs, the increased flexibility for older people to stay in the jobs market would boost the labour market overall Photograph: Christopher Thomond for the Guardian

The White House commission investigating the BP disaster in the Gulf of Mexico began lobbying Congress to set aside anti-government sentiment and commit more funds to overseeing the offshore oil industry. In presenting the commission's final report on the BP disaster, commission co-chair William Reilly said he was launching an all-out campaign to get Congress, the Obama administration and the oil industry to impose tougher safety and environmental regulations Photograph: Sean Gardner/Getty Images

A defiant BAA dismissed accusations of incompetence during the December snow chaos that disrupted Heathrow for five days, affected about a million passengers and cost the airport group £24m. BAA's chief executive, Colin Matthews, said an inquiry was unde rway but so far he had seen no evidence of a fumbled response to a snowstorm that paralysed Britain's largest airport in the last weekend before Christmas. Responding to demands for compensation from airlines including Virgin Atlantic, Bmi and Lufthansa, a combative Matthews said the airport's carriers had agreed to the snow-readiness plan, which had buckled under unprecedented snowfall. Above, airline passengers lay on the floor in Terminal 3 at Heathrow on 19 December Photograph: Luke MacGregor/Reuters

Biscuit maker Burton's Foods is to cut more than 400 jobs – almost one in five of its workforce – and close its factory in Moreton on the Wirral where it makes Jammie Dodgers and Wagon Wheels. The company, which also makes Maryland Cookies and, under licence, Cadbury fingers, blamed the soaring cost of ingredients, such as wheat and cocoa, as well as over-capacity. The Moreton closure will result in a loss of 342 jobs while 70 redundancies are proposed at a factory in Llantarnam, near Newport, south Wales Photograph: Lewis Stickley/PA

A fraudster dubbed a 'British Madoff' pleaded guilty today to a Ponzi scheme fraud that cost investors £14m. Terry Freeman, 62, of Buckhurst Hill in Essex, admitted fraudulent trading, engaging in business while bankrupt, acting as a director when bankrupt and acting in contravention of a disqualification order. Freeman lured 700 investors into his scheme, which collapsed after a last-ditch attempt to recoup its losses by betting on a US bailout of Lehman Brothers. Investors included golfer Colin Montgomerie's ex-wife Eimear, who has said she invested a small amount with Freeman's company, GFX Capital Photograph: Micha Theiner/City AM/Rex Features

After years of bad news and bankruptcy US carmakers were looking forward to the Detroit motor show this year. General Motors, Ford and Chrysler crashed and burned in the last few years. But, after escaping the knacker's yard, the home town car giants put on their most positive performance in years. Some 40 new cars and trucks were unveiled this week, from a new Honda Civic, a mid-sized Volkswagen sedan aimed squarely at the US mass market and even a new Porsche, above Photograph: Stan Honda/AFP/Getty Images

Global leaders received a blunt warning that the world would be unable to cope with an array of potentially 'disastrous' shocks after being left weakened by the financial crisis of 2007-2009. The annual risks survey prepared for the World Economic Forum in Davos later this month identified inequality and weaknesses in global governance as the two key challenges facing policymakers. 'The world is no position to face major, new shocks,' the report noted. 'The financial crisis has reduced global economic resilience, while increasing geo-political tension and heightened social concerns suggest that both governments and societies are less able than ever to cope with global challenges' Photograph: Grigoris Siamidis/Reuters

Move over Warren Buffett, there's a new stockpicker in town – and he has just made $10m (£6.4m) almost overnight. After rapper 50 Cent unveiled a new brand of headphones bearing his name last week, the former drug dealer, whose album Get Rich or Die Tryin' went multi-platinum, used Twitter to tell his 3.8m followers to buy stock in the marketing company – a business he partly owns. H & H Imports has 'one of the 15 products this year. If you get in technically I work for you. BIG MONEY,' he tweeted. 50 Cent, aka Curtis Jackson, added that the 'stock went from 5cent to 10 in one day. You can double your money right now. Just get what you can afford.' His followers evidently took his advice: 9.24m shares were traded in two days and the value increased tenfold Photograph: David Becker/Getty Images