CALGARY — Canada's two largest fertilizer companies say they have received the final regulatory permission required to complete a merger of equals that was originally announced more than 18 months ago.

The combined Potash Corporation of Saskatchewan (POT.TO) and Agrium Inc. (AGU.TO) will be named Nutrien after the deal effectively closes on Jan. 1, subject to customary conditions.

Nutrien's shares are expected to begin trading on the Toronto and New York stock exchanges on Jan. 2 under the symbol NTR. Shares of the two independent companies will be suspended at the same time and delisted.

In order to win approval from the U.S. Federal Trade Commission, Calgary-based Agrium had proposed selling an Idaho-based phosphate production facility and an Ohio-based nitric acid facility.

The FTC announced Wednesday that the commission had accepted the proposed asset sales, subject to public comment until Jan. 29.