The European Union has approved a deal under which General Electric will acquire the energy business of French company Alstom for $12 billion, a source close to the transaction said Monday.

In order to win the green light from the European Commission, GE had to make concessions, the source said.

EU anti-trust regulators had expressed concern the deal could lead to too much concentration in the gas-turbine sector.

A formal announcement is expected Tuesday, the source said.

Approval would end months of uncertainty and tension over the proposed deal, part of a drive by the American conglomerate to stake more of its future on industrial operations.

With the same goal GE is trying to sell its appliances business to Sweden's Electrolux for $3.3 billion.

But the US Department of Justice filed a lawsuit in July to block the Electrolux deal on grounds it would lead to higher prices of key cooking appliances for US consumers.

The GE-Alstom deal had already been approved by the boards of both companies and by the French government.

The Commission had set September 11 as the deadline for it to announce a decision on the GE acquisition, another source told AFP.

The announcement Tuesday will also involve a press conference by EU Competition Commissioner Margrethe Vestager, the source said.

Officials at the Commission and General Electric declined to comment to AFP.