MUMBAI (PTI): The tri-lateral security pact AUKUS will be a "new element" and a game-changer in the Indo-Pacific region, US Deputy Secretary of State Wendy Sherman said in Mumbai on Thursday.

The United States has many other agreements with India so "these pieces do not compete" and the ultimate aim is to keep Indo-Pacific open and free, she said during a virtual interaction.

The US diplomat also said that China is "seeking to undermine" the same international order which enabled its rise for decades.

Sherman, who met business leaders and members of civil society in Mumbai as part of her three-day visit to the country, also said the US is aware of India's concerns about terrorism spilling over from Taliban-ruled Afghanistan.

Quad, a grouping of the US, Japan, India and Australia, is one of the "vehicles" which largely operates in the security realms that are non-military and non-defence, and covers other aspects like vaccines, infrastructure, supply chains and technology too, she said.

AUKUS is a new element of an understanding between the United States, the United Kingdom and Australia to spend the next 18 months considering helping Australia to build nuclear propelled submarines. They are faster, harder to detect, they are more agile and very useful in environment in the Indo-Pacific.

We have lots of other enabling agreements with India. So these pieces do not compete. They are all pieces of a puzzle to ensure that we have an open, free, inter-connected Indo-Pacific, Sherman said, when asked about the place of AUKUS vis-a-vis the Quad.

On Taliban, she said their words must be followed by action, such as preventing reprisals, building an inclusive government and allowing women to work and girls to get education.

And so far they have fallen short of their commitments, she said.

The US appreciates India's concerns about the potential for terrorism to spill over from Afghanistan into the wider region, the diplomat added.

India's rise in the last decade was enabled by the "rules-based international order" and so too was that of China, Sherman said.

The two countries have taken a very different path. Today, Beijing is seeking to undermine the system that benefited them for decades, she said, adding that was why it was important for democracies to deliver results for its people.

As the world's largest vaccine producer, India is a crucial leader in the fight against COVID-19, she said.

Quad members have pledged to donate 1.2 billion vaccines doses globally, in addition to financing even more doses through COVAX, Sherman noted.

Through Quad vaccine partnership, we will support expanded manufacturing at Biological E Ltd with at least 1 billion doses of vaccines by the end of next year, she added.

Sherman arrived on Tuesday on a three-day visit to India. In Mumbai, she met Vice Admiral R Hari Kumar, Western Naval Command's Flag Officer Commanding-in-Chief.