CANBERRA - The Chinese company which purchased the 99-year leasing right for the Port of Darwin announced on Tuesday an $18 million expansion of its operations, just months after taking control of the port.

Landbridge Group, owned by Chinese billionaire Ye Cheng, said it would be expanding its operation in Darwin, with a one-km extension of its quay line among the planned upgrades.

The multi-million dollar development would "expand cruise ship facilities", as well as "meet future increases in cargo volumes in the areas of dry bulk exports, liquid bulk imports, live cattle and container and general cargo throughput," the company said in a statement on Tuesday.

Darwin Port chief executive officer Terry O'Connor said the plan would eventually "quadruple the size of the existing container yard."

The Northern Territory's Chief Minister Adam Giles told the Australian Broadcasting Corporation (ABC) on Tuesday that he welcomed the news of Landbridge's plan as it would increase capacity for extra cruise and cargo routes coming into Australia's far north.

"It is in line with what we wanted to occur with an investor for the port. One of the reasons we pay a lot for goods and services that come over our port, is that our port is not big enough," Giles said.

Giles said Landbridge's plan would also provide a major boost for tourism in the region, allowing the government to show off little-known attractions such as the Kakadu national park.

"To expand the cruise ship terminal to be able to take two cruise ships... to see a new terminal itself, the dredging that'll go on, these are big investments in tourism, which government could never, ever afford to do," Giles said.

Landbridge signed the 99-year lease on the port in October, 2015.