RPT-UPDATE 4-EU blocks Hutchison's deal to buy Telefonica's O2 UK
May 11, 2016 at 12:08 PM EDT
BRUSSELS, May 11 (Reuters) - The European Union's competition regulator blocked on Wednesday CK Hutchison Holdings' plan to become Britain's biggest mobile telecoms network operator, in a decision which also cast doubts on whether it can still win approval for another deal in Italy.