If it's just £300m now it must be a projection as we're not through March yet but quite possible.
Sony UK Ltd has been renamed Sony Europe Ltd. The UK turnover for this pan-European company is:
y/e 31/03/2010: £1.25bn
y/e 31/03/2011: £1.28bn
y/e 31/03/2012: £0.73bn
This excludes Sony Computer Entertainment and the music, mobile, tv and film companies.
And Sony's Bank in Japan. For the past few years the Bank, Sony Music (incl. Sony/ATV publishing) and Sony Pictures have been keeping the company afloat.
Must be quite soul-destroying seeing all the profit your division has made being swallowed into a great big hole, but Sony are hardly alone amongst companies where that's the case.