The Overseas Investment Office is to examine the sale of three big pulp and paper plants to Japanese interests.
Mills at Kinleith, Kawerau and Penrose are being sold by Carter Holt Harvey's owner Graeme Hart, to Oji Holdings Corporation and the Innovation Network Corporation of Japan.
The sale price is $1.037 billion. Oji plans to continue production and retain employees on existing pay and conditions.
The Overseas Investment Office said the sale covers sensitive land and exceeds a $100 million threshold.
No application is in yet, but the OIO has approved big sales in the past of Fisher & Paykel Appliances and Trade Me.