Asciano and the competition watchdog say they need more time to consider rival takeover proposals for the ports and rail operator.
The long running takeover battle for ports and rail operator Asciano will drag on for at least another month as the company and the competition watchdog assess multi-billion dollar bids.
A consortium led by stevedore Qube Holdings is competing with Canadian infrastructure giant Brookfield Infrastructure and its partners to take control of Asciano, which owns the Pacific National rail business and Patrick ports business.
The Australian Competition and Consumer Commission (ACCC) had been due to make a decision on the takeover proposals by February 18, but that has now been delayed to March 24 at the latest.
The watchdog said it requires time to consult on Qube's transaction structure, given the ACCC has only had the details for a very short period.
Qube made an indicative bid for Asciano in November but only formalised its $8.86 billion offer on January 28.
Brookfield's offer came in June and was backed by Asciano's board in August, before the ACCC raised concerns in October and Qube moved soon after to block the transaction.
Asciano said on Friday its board also needs more time to clarify and fully assess some elements of the Qube proposal.
"The board will provide a further update on its consideration of this matter in due course," Asciano said in its first supplementary target's statement.
ACCC chairman Rod Sims said the watchdog also needed more time to consider issues raised by market participants about undertakings offered by Brookfield, and to consider recent revisions of those undertakings.
"We need to consult further with market participants about the proposed divestment of Asciano's Pacific National intermodal rail operations, other vertical integration issues in Western Australia, and undertaking commitments in relation to the Dalrymple Bay coal terminal, and then give Brookfield an opportunity to respond," Mr Sims said.
Pacific National operates across the coal, intermodal (container) and bulk sectors, and provides rail haulage services to the Dalrymple Bay coal terminal near Mackay in Queensland, which is owned by Brookfield Infrastructure.
Mr Sims also said the indicative dates for its decision may be changed again.
The Qube consortium is offering $6.97 in cash plus one Qube share for every Asciano share, which as of January 25 carried a total value of $9.08 per Asciano share .
Brookfield is also offering a cash and scrip deal, comprising $6.94 in cash and 0.0387 Brookfield securities.
Qube says that based upon Brookfield's share price on January 25 and an exchange rate of 69.5 US cents per Australian dollar, Brookfield's offer is worth $8.77 for each Asciano share.
Shares in Asciano were down six cents at $8.84 at 1225 AEDT.