WASHINGTON (Reuters) – The United States on Monday hardened its rejection of China’s disputed claims to offshore resources in most of the South China Sea, calling them “completely unlawful,” in a statement that will further sour the already-fraught ties between the world’s largest two economies.

“We are making clear: Beijing’s claims to offshore resources across most of the South China Sea are completely unlawful, as is its campaign of bullying to control them,” U.S. Secretary of State Mike Pompeo, a prominent China hawk within the Trump administration, said in a statement.

The United States has long opposed China’s expansive territorial claims on the South China Sea, even sending U.S. warships regularly through the strategic waterway to demonstrate freedom of navigation there.

The relationship between the United States and China has grown increasingly tense over the past six months over Beijing’s handling of the coronavirus pandemic, its tightened grip on Hong Kong and its crackdown on China’s Uighur Muslim community.

China has overlapping claims in the energy-rich South China Sea, through which some $3 trillion of trade passes a year with the Philippines, Brunei, Vietnam, Malaysia and Taiwan. Beijing has built bases atop atolls in the region but says its intentions are peaceful.

(Reporting by Humeyra Pamuk, Arshad Mohammed and Daphne Psaledakis; Editing by Leslie Adler)

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