US Defence Secretary Lloyd Austin is on his way to New Delhi for discussions on deepening strategic ties between the two democracies affirming India's role as a key partner in President Joe Biden's focus on the Indo-Pacific to meet China's challenge.

During his visit – the first by a member of Biden's cabinet – that starts on Friday he is to meet with Defence Minister Rajnath Singh and National Security Advisor Ajit Doval.

Austin will come to India after visiting two US treaty allies, Japan and Korea, on the frontlines of Chinese aggressiveness at sea in the region, and the military headquarters of the Indo-Pacific headquarters in Hawaii.

Last week Biden held a virtual summit with other leaders of the Quad, Prime Ministers Narendra Modi of India, Scott Morrison of Australia and Yoshihide Suga of Japan, at which they discussed security issues in the face of Chinese aggressive actions.

It was his first multilateral summit indicating his priority to the region.

Outlining Austin's agenda in India, Acting Assistant Defence Secretary for Indo-Pacific, David F. Helvey, said that he will “discuss operationalising the major defence partnership that we have with India, including through enhanced information sharing, regional security cooperation, defence trade, and cooperation in new domains.”

The Indian Defence Ministry said that Singh and Austin “are expected to discuss ways to further strengthen bilateral defence cooperation and exchange views on regional security challenges and common interests in maintaining a free, open and inclusive Indo-Pacific region.”

It added, “Discussions regarding defence cooperation would also focus on how both countries could consolidate military-to-military cooperation and defence trade and industry cooperation.”

India and the US have signed several important agreements to enhance defence cooperation and US arms sales to India reached $20 billion last year.

While India is not a treaty partner of the US, it was designated as a major defence partner by the US in 2016 allowing it access to some defence hi-tech that would normally be available only to allies.

This will be the first major interaction with India for Austin, who retired as a four-star general after a 41-year career in the US Army during which he had not served in Asia.

In discussing Pakistan and Afghanistan with India, Austin will bring special insights as he had headed the US Central Command that covered those two countries.

While Biden is concerned about the dangers from China to the US and to the region, others in his party have their own agenda for India.

Bob Menendez, the chair of the Senate Foreign Relations Committee, has written to Austin raising the farmers' agitation, Kashmir, Citizenship Amendment Act (CAA) and intimidation of journalists and government critics.

He characterised the CAA, which gives expedited citizenship to Hindus, Christians, Buddhists and Sikhs fleeing religious persecution, and the abrogation of Kashmir's special status as “anti-Muslim.”

In what amounts to an ultimatum to India, Menedez wrote in the letter posted on his committee's website that Austin should make clear to India that “security cooperation, the US-India partnership must rest on adherence to democratic values.”

He warned of sanctions if India went ahead with the Russian-made S-400 Triumf missile defence system.

It “will clearly constitute a significant, and therefore sanctionable, transaction with the Russian defence sector under Section 231 of CAATSA (Countering America's Adversaries Through Sanctions Act). It will also limit India’s ability to work with the U.S. on development and procurement of sensitive military technology.”

CAATSA imposes sanctions for dealing with some Russian companies and India will need an exemption for the S-400 deal.

But he also acknowledged that “Getting the U.S.-India partnership right is critical to addressing 21st century challenge.”