Britain's competition regulator said on Friday it had cleared Boeing's planned acquisition of Spirit AeroSystems after deciding against an in-depth investigation into whether the deal would be anti-competitive.

The UK's Competition and Markets Authority did not provide details in its initial statement, which said the probe would not go to a so-called "phase 2". The full text of its decision would be published shortly, it said.

The watchdog had started its initial investigation in June and had a deadline of August 28 for a decision.

Boeing and Spirit did not immediately respond to Reuters' requests for comment.

The planemaker had agreed to buy back Spirit AeroSystems for $4.7 billion in stock last year, marking an end to a near-two-decade independence of the world's largest standalone aerostructures company.

(Reporting by Pushkala Aripaka, Nithyashree R B and Prerna Bedi in Bengaluru; Editing by Sonia Cheema and Shilpi Majumdar)