As US President Joe Biden prepares for a summit with Indian Prime Minister Narendra Modi and other leaders of the Quad, the top American commander in the Indo-Pacific region has said that China's aggression has opened New Delhi's eyes to the advantages of strategic cooperation with Washington and other countries and it will deepen ties with the four-nation group.

"India's long had an approach called strategic autonomy, you know non-aligned approach with others. But I think certainly the activities (of China), along the Line of Actual Control (LAC) with China has opened their eyes to what cooperative effort with others might mean for their own defensive needs," Admiral Philip S. Davidson, head of the US Indo-Pacific Command, said on Tuesday.

"We have provided some information to Indian that crisis, cold weather clothing, some other equipments and things like that. And over the last several years we've been deepening our maritime cooperation.

"I think you'll see India in the very near term, you know, remain committed to their non aligned approach, but I think they will deepen their engagement with Quad," he added.

While testifying on the Indo-Pacific Command Posture before the Senate Armed Services Committee, he was replying to a question by Senator Angus King whether the US was developing stronger ties with India, which considers itself "neutral" as a part of the Quad.

The leaders of the Quad, Modi, Biden and Prime Ministers Scott Morrison of Australia and Yoshihide Suga of Japan are to meet virtually for their first summit on Friday as they mutually face the growing threat from China.

"The Indo-Pacific is the most consequential region for America's future and remains the Department of Defense's priority theatre," Davidson said of the US pivot to the region that began with former President Donald Trump and Biden appears committed to, recognising the threat from China.

Davidson said that he had great hope that the Quad, "a diamond of democracies", will "build into something much bigger for the sake of the globe".

He said that the Quad "could bring so much more, not only to the region (but) to the globe, not in terms of security alone, but in terms of how we might approach the global economy, critical technologies like telecommunications and 5G, collaboration on international order, more diplomatically, economically".

King said it would "be a geopolitical major development if India more closely aligned with those other countries" of the Quad.

Committee Chairman Jack Reed said that growing relations with India and other countries in the Indo-Pacific region would give the US a comparative advantage in the region in facing the threats from China.

"Absent a convincing deterrent, the People's Republic of China (PRC) will be emboldened to take action to undermine the rules-based international order and the values represented in our vision for a Free and Open IndoPacific," Davidson said.

Davidson and senators on the committee spoke of China's direct threats to India.

He said that China's "expansionary territorial ambitions" can be seen along the LAC where, he said, "the PLA has been engaged in a standoff with Indian forces".

"The standoff was predicated by clashes over construction activities near the disputed border," last May, he said.

Beijing "forward-deployed roughly 50,000 soldiers along the LAC, leading to a counter-deployment by the Indian Army" and China "has not yet withdrawn from several forward positions it seized following the initial clash, and the consequent escalation of tensions between the PRC (People's Republic of China) and India has resulted in casualties on both sides", he added.

"This large-scale PLA mobilization, which is particularly notable considering the elevation, terrain, and distance involved, has stoked regional concerns that the PRC will increasingly use force to achieve desired outcomes," he added.

Senator Dan Sullivan listed the border conflict with India and major cyber attacks "that were probably launched by China against India" as among the threats the world faces.

Davidson warned that the Islamic State terror group, "which remains the most active and deadliest terrorist threat in the region", has branches in India and the Philippines and India.

"Notably, these disparate IS and IS-inspired groups are not cohesive; they do not collaborate or fall under the same command and control structure."