Describing the Chinese military's activities in the region as "destabilising", US Secretary of Defence Mark Esper on Tuesday said America was "very closely" monitoring the situation between India and China along the Line of Actual Control.
Mr Esper made the remarks while addressing a virtual security seminar amid China's renewed military assertiveness in eastern Ladakh as well as in the South China Sea.
"We are obviously monitoring the situation between India and China very closely, what's happening along the Line of Actual Control and we are very pleased to see both sides are trying to de-escalate the situation," Mr Esper said in response to a question on the tension between the two countries.
Asserting that the People's Liberation Army activities in the region are "destabilising", he said that it "continues its aggressive behavior in the East and South China Seas."
Mr Esper also said that America's relationship with India is "one of the all-important defence relationships of the 21st century".
In the midst of India's border row with China, a US Navy carrier strike group led by nuclear-powered aircraft carrier USS Nimitz carried out a military drill with a fleet of Indian warships off the coast of Andaman and Nicobar Islands on Monday.
Four frontline warships of the Indian Navy participated in the "PASSEX" exercise when the US carrier strike group was transiting through the Indian Ocean Region on its way from the South China Sea, officials in New Delhi said.
The USS Nimitz is the world's largest warship and the exercise between the two navies assumed significance as it took place in the midst of tensions between India and China in eastern Ladakh as well as in China's military assertiveness in South China Sea.
Mr Esper said that the joint exercise in the Indian Ocean shows growing cooperation between the naval forces of India and the US.
"I want to highlight our increased defence cooperation with India, one of the most important defence relationships of the 21th century. We conducted our first-ever joint military exercise last November. As we speak today, USS Nimitz is conducting a combined exercise with Indian Navy in the Indian Ocean, demonstrating our shared commitment to stronger naval cooperation and support to a free and open Indo-Pacific," he said.
"Our carriers have been in the South China Sea and Indo-Pacific since World War II. We will back the sovereignty of our friends and partners," he added.
Mr Esper said China's unlawful land reclamation and military exercises on and around disputed features in the South China Sea are patently inconsistent with its commitments set out in the 2002 Declaration on the Conduct of Parties in the South China Sea.
"The Chinese Communist Party continues to engage in systemic rule-breaking, coercion and other malign activitiesm," he said, adding that it has bullied ASEAN nations out of an estimated USD 2.6 trillion in potential offshore oil and gas revenue and denied them access to important fishing grounds.
China has been fast expanding military and economic influence in the Indo-Pacific region, triggering concern in various countries of the region and beyond.
China is also engaged in hotly contested territorial disputes in both the South China Sea and the East China Sea. Beijing has built up and militarised many of the islands and reefs it controls in the region. Both areas are stated to be rich in minerals, oil and other natural resources and are vital to global trade.
China claims almost all of the South China Sea. Vietnam, the Philippines, Malaysia, Brunei and Taiwan have counter claims over the area.
Mr Esper asked the Chinese leaders to abide by the international laws and norms that China ~CHECK~ and the Chinese people ~CHECK~ have benefited greatly from over the years. "And while we hope the CCP will change its ways, we must be prepared for the alternative," he cautioned.
He said the US policy on the South China Sea "champions a free and open Indo-Pacific...and makes clear that the People's Republic of China has no right to turn international waters into a zone of exclusion or its own maritime empire."
"We must uphold the free and open system that has secured peace and prosperity for millions: respect for sovereignty; peaceful resolution of disputes; adherence to international laws and norms; and promotion of free, fair and reciprocal trade," he said.
"We firmly believe no single nation can ~CHECK~ or should ~CHECK~ dominate the public commons, and we will continue to work alongside our allies and partners to support a prosperous and secure Indo-Pacific for all," Mr Esper said.
Mr Esper also said that the US "commitment to free and open Indo-Pacific rooted in values, history and economic ties we share with allies and partners, and has only grown deeper in the face of efforts to undermine it."
"We are encouraging Indo-Pacific nations to expand their own intra-regional security relationships and networks of like-minded partners," he added.
Navies from the US, India, Australia, Japan and France have been deepening their mutual cooperation in the Indo-Pacific region in view of China's growing attempt to expand military influence in the resource rich region.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)