The Fay consortium still intends to seek a judicial review if the Chinese consortium gets approval.
Peter McCarthy from Crown Law said a decision is due late tonight or tomorrow.
The parties are to hold a telephone conference at noon on Monday.
The sale involves 8,000 hectares of North Island farmland. Its sale to a foreigner has been controversial.
The Fay-led consortium, including Tiroa E and Te Hape B Trusts, Tauhara Hapu Trusts, Aitchison Farms, WD Holmes 2000 Trust, Donovan Group and Brent Cook launched a rival $171.5 million offer in September, believed to be some $30 million below Pengxin's bid.
The Fay group had its bid for the farms declined by receiver KordaMentha, who called the price "unacceptable".
Prime Minister John Key said yesterday that he hasn't seen anything to make him question the OIO's processes.
Key has talked down the extent of foreign ownership of local farmland, saying he understood it to be less than 1 per cent.
"The wholesale sale of land in New Zealand is not in New Zealand's best interests, and that was why we sought to toughen up the overseas investment act," he said. "At around about 1 per cent, I don't think we have a substantial issue."