Tuesday's announcements came after talks in New Delhi between India's Foreign Minister Subrahmanyam Jaishankar, US Secretary of State Marco Rubio, Japanese Foreign Minister Toshimitsu Motegi and Australian Foreign Minister Penny Wong.
Speaking after the meeting, Rubio announced a new Indo-Pacific maritime surveillance initiative to integrate the four countries' surveillance capabilities and strengthen real-time information sharing across the region.
Rubio also said the Quad would work with Fiji to upgrade port infrastructure in the Pacific islands, marking its first joint regional infrastructure project.
The ministers also launched an Indo-Pacific energy security initiative aimed at strengthening regional fuel and energy supply chains, with the US set to host a Quad fuel security forum later in 2026, Rubio said.
"We are deeply committed to this partnership. It is a linchpin in a cornerstone of our global strategy as a nation," he said.
Australia, India, Japan and the US make up the Quad group, a key strategic partnership for co-operation on maritime security, supply chains and regional strategy as China expands its military and economic influence in the Indo-Pacific.
The Quad has repeatedly accused China of flexing its military muscles in the South China Sea and aggressively pushing its maritime territorial claims.
Beijing maintains its military is purely defensive to protect what it says are China's sovereign rights and calls the Quad an attempt to contain its economic growth and influence.
Senator Wong said the Indo-Pacific was facing "acute economic stress" and warned any closure of the strait would have serious consequences for regional energy security.
"We recognise the importance of maintaining the principle of freedom of navigation and our opposition to any tolling proposition," Wong said, referring to Iran's plan to charge vessels passing through the Strait of Hormuz.
She said the Quad reflected a shared commitment among four sovereign nations to a free and open Indo-Pacific.
"There is great alignment between our interests. We all share a vision for the Indo-Pacific, a region that is free and open," she said.
The meeting comes days after US President Donald Trump visited China, a trip closely watched in New Delhi for signs of any shift in Washington's approach toward Beijing.
The four countries had hoped to hold a leaders' summit in India in 2025, but the plan was delayed because of strains in US-India relations, including disagreements over tariffs.
