General Electric has finally secured approval for its purchase of Alstom following a protracted period of negotiation aimed at satisfying European regulators that the deal would not lead to a monopoly.

The approval of the $13.5bn deal was announced in Strasbourg, France, by Margrethe Vestager (below right), the European Union competition commissioner, who expressed satisfaction that the concessions made by the US multinational meant anti-trust rules were satisfied.

CEO Jeff Immelt and his team had succeeded first in persuading the French government in approving the deal but there had been fears that EU regulators would scupper its ultimate progress. This had occurred in 2001 when GE tried and was denied acquiring Honeywell.

The deal will  help G.E. extend its leading role in the business of providing electrical utilities with generating equipment and power-grid infrastructure at a time the world is increasingly moving away from dirty coal and toward cleaner natural gas, solar and wind energy.

GE’s Alstom assets, in particular the gas and steam turbine businesses, would strengthen the American company’s footing in emerging markets like China and India. G.E. is also obtaining sophisticated technology in renewable energies and grid infrastructure, as well as the French company’s expertise in power-plant design.

Alstom’s power unit makes equipment for generating and distributing electricity for utilities across the globe. The main prize for G.E. is Alstom’s heavy-duty gas turbines business, which holds lucrative contracts worldwide for servicing installed power plants.

Because G.E. is already the world leader in that field, its main rival in Europe, Siemens, had argued to antitrust officials that the deal would leave too much of that market in the hands of the American company. GE Alstom

To win the commission’s approval, General Electric agreed to sell a number of assets to Ansaldo Energia, an Italian engineering company that builds and services power plants. The assets to be divested include two models of gas turbines and various service contracts in Europe. Ansaldo will also buy Alstom’s Power Systems Manufacturing unit, which makes parts for servicing gas turbines.

Ms. Vestager, referring to the size of the overall transaction, said at a news conference in Strasbourg that, “In my book, this is a big deal.” The divestitures would avoid “a great risk of choice going down and prices going up,” she said.

The conditions required for the approval by the European authorities showed that “Europe is open for business,” but also that “you cannot buy yourself into a monopoly,” she said.