Washington, Jul 14 (IANS): US Secretary of State Mike Pompeo has said that China's pursuit of offshore resources in parts of the South China Sea was "completely unlawful".

In a statement on Monday, Pompeo denounced China's claims on the disputed Spratly Islands in the South China Sea, saying Beijing had "no legal grounds to unilaterally impose its will on the region", the BBC reported.

He said the US, which has previously said it does not take sides in territorial disputes, rejected China's claims to waters off Vietnam, Malaysia and Indonesia.

"Any (People's Republic of China) action to harass other states' fishing or hydrocarbon development in these waters - or to carry out such activities unilaterally - is unlawful," he said.

"The world will not allow Beijing to treat the South China Sea as its maritime empire."

Although largely uninhabited, the two island chains in the area may have reserves of natural resources around them. The sea is also a shipping route and has major fishing grounds, said the BBC report.

China has been building military bases on artificial islands in the region also claimed by Brunei, Malaysia, the Philippines, Taiwan and Vietnam.

Beijing claims an area known as the "nine-dash line" and has backed its claim with island-building and patrols, expanding its military presence there.

Responding to Pompeo's statement, the Chinese Embassy in Washington D.C. said on Twitter that the US State Department "deliberately distorts the facts and international law including the United Nations Convention on the Law of the Sea".

It said America "exaggerates the situation in the region and attempts to sow discord between China and other littoral countries".

"The accusation is completely unjustified. The Chinese side is firmly opposed to it," the BBC quoted the Embassy as saying.

The US has long been critical of what it says is China's militarisation of the region and routinely angers Beijing with "freedom of navigation" missions.