FMC Technologies and Technip been cleared by the European Commission to go ahead with a merger.
The firms are set to combine, with shareholders due to vote on the move, announced back in May, on 5 December.
Clearance decisions have previously been issued by antitrust authorities in the US, India, Turkey, Mexico and Russia.
The merger remains subject to other closing conditions, including approval of FMC Technologies and Technip shareholders, as well as certain antitrust and regulatory approvals and customary closing conditions.
The deal is expected to close early 2017, subject to these conditions.