US Envoy Warns China Is Weaponizing Maritime Power as Greenland Debate Intensifies

Warren Stephens warned of threats to ports, shipbuilding, Panama, and Arctic security as Washington presses allies on maritime vulnerabilities.

Arsenio Domínguez, secretary-general of the International Maritime Organization, welcomes Ambassador Warren Stephens as the U.S. permanent representative to the IMO on July 7, 2026. Courtesy of Ambassador Warren Stephens

U.S. Ambassador to the UK Warren Stephens warned the International Maritime Organization that Beijing is using maritime infrastructure and commercial dominance as tools of political pressure, placing the Trump administration’s Greenland push inside a wider debate over Arctic security and the vulnerability of ports, ships, and supply chains.

Stephens, who also serves as U.S. permanent representative to the International Maritime Organization (IMO), said in a July 7 statement to the IMO Council that China’s maritime reach is “a challenge that this body cannot afford to ignore.”

He said China “currently builds more than half of the world’s ships,” dominates production of ship-to-shore cranes and shipping containers, and has pursued port concessions and infrastructure worldwide, “not simply for commercial gain,” but to extend its strategic reach and weaponize access against sovereign nations.

The remarks came days after President Donald Trump renewed calls for U.S. control of Greenland at the NATO summit, saying the Arctic island “should be controlled by the United States, not by Denmark.” Trump has cited Chinese and Russian activity in Arctic waters as part of his national-security rationale.

Denmark and Greenland have rejected a U.S. takeover. Danish Prime Minister Mette Frederiksen said on July 8 that Greenland is “not for sale” and that Denmark would defend every inch of NATO territory, including its own.

Stephens said the United States would continue advocating at the IMO for maritime safety and security, freedom of navigation, sanctions enforcement, polar-operation standards, autonomous-vessel rules, and cyber-risk management.

He linked those priorities to Trump’s maritime policy, saying the president’s executive order established a plan to rebuild U.S. shipbuilding, expand the commercial fleet, strengthen the maritime workforce, and ensure shipping capabilities support economic independence and national security.

Trump signed the maritime executive order in April 2025. The Office of the U.S. Trade Representative (USTR) separately took action that month after a Section 301 investigation concluded that China’s policies in the maritime, logistics, and shipbuilding sectors were unreasonable and burdened U.S. commerce.

“At the IMO, the United States will continue to champion” freedom of navigation and the rule of law, Stephens said, calling them “the bedrock principles without which international trade cannot function.”

Panama Cited as Warning

Stephens pointed to Panama as a recent example of the vulnerability created when foreign powers or their proxies control critical port infrastructure.

Panama’s Supreme Court ruled that CK Hutchison’s port concessions at the Balboa and Cristóbal terminals were unconstitutional. The two terminals are among the most strategically significant ports at the Panama Canal.

“China’s response was swift and punishing,” Stephens said, adding that Beijing took direct action against Panama-flagged vessels. He said the United States characterized those actions as an attempt to undermine Panama’s sovereignty, disrupt global supply chains, and erode confidence in international trade.

The United States, Bolivia, Costa Rica, Guyana, Paraguay, and Trinidad and Tobago issued a joint statement in April supporting Panama’s sovereignty and opposing efforts to politicize maritime trade.

“What happened to Panama is a warning to every nation in this room,” Stephens said.

“The pattern is consistent: China uses its maritime and economic power to coerce, to intimidate, and to punish those who assert their sovereign rights,” he said.

Greenland and the Arctic

Greenland sits between the North Atlantic and the Arctic and hosts Pituffik Space Base, formerly Thule Air Base, on its northwest coast. The U.S. Space Force says the base is the Defense Department’s northernmost installation and supports force protection, space superiority, and scientific research in the Arctic.

The United States has also expanded its diplomatic presence in Greenland. The U.S. Embassy in Denmark said Ambassador Kenneth Howery traveled to Greenland in May to open the U.S. Consulate’s new office space in Nuuk.

Louisiana Gov. Jeff Landry, who also serves as special envoy to Greenland, said earlier this month that Trump “has not forgotten” Greenland and that Washington should deepen military, trade, shipping, and air links with the island.

Denmark has also moved to strengthen its Arctic posture. The Danish Ministry of Defense announced on Jan. 27, 2025, that political parties behind the Danish Defense Agreement had approved a first Arctic and North Atlantic package worth 14.6 billion Danish kroner (about $2.1 billion).

The package includes three Arctic naval vessels, two long-range drones, satellite capacity, ground-based sensors, expanded Arctic basic military training, and upgrades to the Joint Arctic Command in Nuuk.

Danish Defense Minister Troels Lund Poulsen said at the time that Denmark had to face “serious challenges regarding security and defence in the Arctic and North Atlantic.” Vivian Motzfeldt, Greenland’s minister of statehood and foreign affairs, said Greenland was facing “a changing security landscape.”

Call for Greater Scrutiny

Stephens urged IMO members to carefully scrutinize agreements granting foreign—particularly state-linked—entities control over critical port infrastructures.

“Transparency, the rule of law, and genuine sovereignty are not obstacles to commerce,” he concluded. “They are its foundation.”

He called on the IMO to strengthen frameworks for maritime security, sanctions enforcement, and protection of flag-state rights, warning against allowing coercive actors to exploit procedural weaknesses.