SYDNEY - [AAP] A healthy September quarter on the back of surging gaming revenue has not helped accelerate Tabcorp's (ASX: TAH) stalled merger with Tatts Group (ASX: TTS).

Tabcorp lifted first-quarter revenue 5.7 per cent to $578.8 million, after gaming services revenue surged 47.8 per cent to $41.4 million for the first quarter of 2018, chief executive David Attenborough said.

Mr Attenborough told shareholders, at the company's AGM in Melbourne on Friday, that total wagering turnover for the three months to September 30 was up 3.5 per cent at $3.1 billion.

While wagering and media was up 4.5 per cent and Keno revenue had slipped 5.3 per cent, Tabcorp's FY18 priorities were centred on the successful completion of the proposed Tatts combination, Mr Attenborough said.

Tabcorp chairman Paula Dwyer said the Australian Competition Tribunal had this week finished considering the proposed transaction for a second time after originally approving the merger in a June decision that was challenged by the Australian Competition and Consumer Commission and rival CrownBet.

Crownbet's claim had been dismissed, while an aspect of the ACCC's grounds for review was upheld and the matter referred back to the Tribunal for redetermination, she said.

Ms Dwyer conceded to shareholders that the drawn-out union with Tatts Group was accumulating costs but the board was prepared for the outcome with the redetermination ruling expected at any time.

"These costs have not been incurred lightly," Ms Dwyer said.

"While this is a complex transaction, it is the result of a considered decision by the board, weighing the inherent risks in undertaking a transformational transaction of this size against the significant benefits of the proposed combination."

Meanwhile, Tabcorp's Sun Bets investment with News UK, opening up the UK online wagering and gaming market has "so far disappointed," despite revenue lifting 5.3 per cent.

Ms Dwyer said the business did not deliver according to plan and had been reset for growth, or earmarked for exit.

"If performance does not improve to meet forecast expectations, we will give serious consideration to exercising our contractual right to exit operations from 31 December 2019," Ms Dwyer said.

© [2017] Australian Associated Press Pty Limited (AAP) or its Licensors. This is the Morningstar service with content provided by AAP where indicated. AAP reserves all rights, including copyright, in services provided by it. The information in the service is for personal use only, does not constitute financial product advice (whether general or personal) and may not be re-written, copied, re-sold or re-distributed, framed, linked or otherwise used whether for compensation of any kind or not, without the prior written permission of AAP. You should seek advice from a professional financial adviser before making decision to acquire or dispose of a financial product.

This service is published for general information purposes only without assuming a duty of care. AAP is not in the business of providing financial product advice (whether personal or general advice), and gives no warranty, guarantee or other representation about the accuracy of the information or images contained in this service. AAP is not liable for errors, omissions in, delays or interruptions to or cessation of the services through negligence or otherwise. The globe symbol and "AAP" are registered trademarks.