(Reuters) - Australia's competition watchdog dropped its opposition to a $4.7 billion takeover offer for lottery owner Tatts Group (>> Tatts Group Limited) from horse-race betting firm Tabcorp Holdings (>> Tabcorp Holdings Limited), clearing the regulatory path for a long-pending deal.

The Australian Competition and Consumer Commission (ACCC) said on Friday it has decided not to apply for a judicial review of a decision by the Australian Competition Tribunal to allow Tabcorp's bid for Tatts Group to proceed.

The deal was cleared in June by the tribunal, a court-affiliated body, but the ACCC appealed the decision and an Australian court asked the tribunal to reconsider its decision.

Last month, the tribunal once again cleared the proposed takeover, dismissing concerns raised by the ACCC, the country's default M&A regulator.

The deal has been mired in uncertainty since Tabcorp and Tatts Group announced their plans 13 months ago, their third such attempt after having failed twice since 2006.

A Tabcorp-Tatts union would create a gambling powerhouse at a time of rising competition from rivals such as Britain's William Hill (>> William Hill) and Ireland's Paddy Power (>> Paddy Power Betfair PLC).

Tabcorp and Tatts, in separate statements, said on Friday the deal's competition condition had been waived, leaving approval from Tatts' shareholders and consideration by the Supreme Court of Victoria as the only remaining hurdles to the deal going through.

Tabcorp also said the expected date for the deal's implementation would be Dec. 22. Tatts said its board "continues to unanimously recommend" Tabcorp's offer in the absence of a superior offer.

Tabcorp shares closed up 1.4 percent on Friday, while Tatts gained 0.7 percent.

(Reporting by Aaron Saldanha and Chandini Monnappa in Bengaluru; Editing by Muralikumar Anantharaman)

By Aaron Saldanha and Chandini M