The 10 biggest business stories on Thursday March 17

Osborne hits back at Budget critics; Toshiba shares plunge on US probe reports

Toshiba shares tumbled nearly 10% on Thursday after Bloomberg News reported that Toshiba was under investigation by US authorities

1. The chancellor's promise to return public finances to the black by 2020 is to come under scrutiny by experts and MPs after his Budget featuring a sugar tax and gloomy economic forecasts. The influential Institute for Fiscal Studies will examine the chances of the deficit being cleared by 2019-20.

2. The US Federal Reserve's policy-setting committee left its benchmark interest rate unchanged at its two-day meeting.

3. Sir Andrew Witty, GlaxoSmithKline chief executive, will leave the company in March 2017, the pharmaceuticals giant said today.

4. Toshiba shares tumbled nearly 10 per cent on Thursday after Bloomberg News reported that Toshiba was under investigation by US authorities over accounting related to its Westinghouse nuclear power operations.

5. Ted Baker said new store openings and strong demand helped it post a jump in full-year profit, and its spring and summer collections had received a positive customer response. Profit before tax and exceptional items rose 18.6 per cent to £58.7 million pounds for the year to January 30, with revenue up 17.7 per cent to £456.2 million.

6. Rio Tinto, the FTSE 100 listed miner company has named coal and copper boss Jean-Sébastien Jacques as chief executive Sam Walsh’s successor.

7. Asda has confirmed plans to cut up to 500 jobs in stores and 250 at its head office in Leeds as the retailer battles to protect profits while sales slide, the Guardian reports.

8. The European Commission has asked tax authorities in Ireland for additional information on Apple's tax affairs in the country, according to The Irish Times.

9. Lufthansa, the German airline group, forecast slightly higher profits in 2016 thanks to lower fuel prices, but warned of price pressure from rivals and falling ticket yields as it ramps up its Eurowings budget unit.

10. A FedEx VP told analysts that it would take too long and cost too much for Amazon to build a delivery service that competes with its own. He said Amazon would have to spend “tens of billions.” Business Insider reports.