Describing the move as "strengthening U.S. policy," the top US diplomat asserted that "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."
"The world will not allow Beijing to treat the South China Sea as its maritime empire. America stands with our Southeast Asian allies and partners in protecting their sovereign rights to offshore resources, consistent with their rights and obligations under international law," Pompeo said in a lengthy statement.
Beijing claims almost all of the 1.3 million square mile South China Sea as its sovereign territory and over the past several years has built up military fortifications on several islands.
But specific islands and waters in the South China Sea are claimed by several states and islands that surround it, including the Philippines, Vietnam, Malaysia, Indonesia, Brunei and self-governing Taiwan.