Chinese investors have added another 50,000 hectares to their Australian property portfolio, taking the total area of property under Chinese control to more than 9.1 million hectares amid growing concerns over foreign interference and national security.

China is now the second largest investor in Australian land and is within a million hectares of the top landholder, the United Kingdom, as Canberra moves to tighten controls over foreign investors.

The Bahamas has rocketed up the standings after a company or individual based in the tax haven finalised the mysterious purchase of more than 2 million Australian hectares, almost twice the size of the Caribbean island itself.

China continues to be a major foreign buyer. Credit:Photo: Glenn Hunt

Treasurer Josh Frydenberg said while foreign investment was an important contributor to growth, productivity and jobs in agricultural communities, "it is important to ensure that foreign investment is not contrary to the national interest".