Recent months have seen European regulators go cold on mobile mergers, especially those which reduce the number of operators in a country, and Sharon White, new CEO of UK regulator Ofcom, reflected that mood when voicing new concerns about the proposed acquisitions of EE by incumbent telco BT, and of O2’s UK arm by Hutchison Three. White told an audience at the London School of Economics that, unlike some markets, the UK was still delivering good returns for four MNOs, with average cashflow margins above 12% despite recent high investments in LTE. “We continue to believe that four operators is a competitive number that has delivered good results for consumers and sustainable returns for companies,” she said. “I am concerned…