Toronto’s TMX Group and the London Stock exchange announced on Wednesday they will be merging. Xavier Rolet, currently the LSE’s CEO, will become the chief executive of the merged group. The combined fiscal clout of the new group is substantial – both groups have 6,700 listings combined, meaning a collective market value of $5.8-trillion. But the merger only puts the LSE-TMX group seventh on the global trading stage, beneath the Honk Kong Exchanges, Exchanges & Clearing Group and Deutsche Borse. While critics call the merger a “defensive” action to cut costs that diverts management’s attention from developing growth strategies, executives involved say it is seizing a growth opportunity that will create a global leader in resource and energy stocks. The deal will require the approval of government departments in Canada and the U.K., including Investment Canada, the Ontario and Quebec securities commission and the Financial Services Authority. If approved, the TMX-LSE group will become the trading leader in the European Union.