State-controlled Enel and CDP had until now shared ownership of Open Fiber, which had been set up to roll out fibre optic cables to close Italy's digital divide with the rest of Europe.

The EU competition enforcer set a Nov. 10 deadline for its decision.

The deal will up CDP's Open Fiber stake by 10% to 60% while Macquarie will acquire 40%.

(Reporting by Foo Yun Chee; Editing by Kirsten Donovan)