Sri Lanka tops the list of nations that may host a Chinese naval base in the coming years as Beijing seeks to expand its maritime capabilities, according to a new report.

The South Asian nation’s Hambantota port is the most likely spot for a base given the $2.19 billion China has already invested there, according to an assessment by the AidData research project at William & Mary university in Virginia.

China’s People’s Liberation Army Navy (PLAN) currently only has one overseas military base in Djibouti, on the coast of the Horn of Africa.

But as the rivalry between the US and China heats up, Beijing is catching up with Washington’s overseas maritime strength. Unlike the US, China is not party to international defence alliances – its only formal defence treaty is with North Korea. That makes developing overseas naval bases a priority for China’s military development, argue the AidData researchers.

PLAN’s future ambitions may be closely aligned with China’s belt and road initiative. Four of the eight bases shortlisted by AidData are in Africa. Although China’s most pressing maritime ambitions are in the South China Sea and the Taiwan strait the report’s authors note that those operations could be conducted “entirely from the Chinese mainland and home naval bases”. PLAN bases farther afield would help China to preserve shipping routes, especially in the event of western sanctions, and gather intelligence.