Secretary of State Marco Rubio says President Donald Trump’s desire to acquire Greenland and retake control of the Panama Canal is driven by legitimate national security interests stemming from growing concerns about Chinese activity and influence in the Arctic and in Latin America.

US senators heard sharply different analyses about Chinese influence over the Panama Canal on Wednesday, with some experts suggesting solutions ranging from enhanced trade partnerships to military intervention to regain control of the strategic waterway.

The Tuesday hearing delved into security issues and foreign influence on the foremost maritime channel connecting the Atlantic and Pacific Oceans.