This statement was made by the press office of the State Department. According to it, the US government gave TransCanada a permit for the construction, connection, management and maintenance of the pipeline on the US-Canadian border in Phillips County, in Montana, for the purpose to import crude oil.
Now the company must obtain similar permit to extend a string of the pipeline to the territory of Nebraska.
The President of the United States, Donald Trump, is expected to make a statement soon on this matter.