Indian Prime Minister Narendra Modi has met with US and Indian technology executives in Washington on the final day of a state visit during which he agreed new defence and technology co-operation and addressed challenges posed by China. US President Joe Biden rolled out the red carpet for Modi on Thursday, declaring after more than two hours of talks that their countries' economic relationship was "booming". Trade between the two countries has more than doubled during the past decade. Biden and Modi gathered with CEOs including Apple's Tim Cook, Google's Sundar Pichai and Microsoft's Satya Nadella. Also present were Sam Altman of OpenAI, NASA astronaut Sunita Williams, and Indian tech leaders including Anand Mahindra, chairman of Mahindra Group, and Mukesh Ambani, chairman of Reliance Industries, the White House said. "Our partnership between India and the United States will go a long way, in my view, to define what the 21st century looks like," Biden told the group, adding technological co-operation would be a big part of that partnership. Observing that there were a variety of tech companies represented at the meeting from startups to well-established firms, Modi said: "Both of them are working together to create a new world." Modi, who has appealed to global companies to "Make in India", will also address business leaders at the Kennedy Center for Performing Arts. The CEOs of top American companies, including FedEx, MasterCard and Adobe, are expected to be among the 1200 participants. The backdrop to Modi's visit is the Biden administration's attempts to draw India, the world's most populous country at 1.4 billion and its fifth-largest economy, closer amid its growing geopolitical rivalry with Beijing. Modi did not address China directly during the visit, and Biden only mentioned China in response to a reporter's question, but a joint statement included a pointed reference to the East and South China Seas, where China has territorial disputes with its neighbours. In an analysis note, Asia Society Policy Institute director for South Asia Farwa Aamer described that as "a clear signal of unity and determination to preserve stability and peace in the region". Alongside agreements to sell weapons to India and share with it sensitive military technology, announcements this week included several investments from US firms aimed at spurring semiconductor manufacturing in India and lowering its dependence on China for electronics. White House national security spokesman John Kirby said the challenges presented by China to both Washington and New Delhi were on the agenda, but insisted the visit "wasn't about China". "This wasn't about leveraging India to be some sort of counterweight," Kirby said at a news briefing, adding that Washington welcomes India becoming "an increasing exporter of security" in the Indo-Pacific. "India is a sovereign, independent state. "There's a lot we can do in the security front together and that's really what we're focused on." Australian Associated Press