Military bands and horse and camel cavalry units paraded through capital New Delhi, while fighter jets buzzed overhead and India's latest military hardware was put on display.

"The occasion inspires us in our collective resolve to build a developed India," Prime Minister Narendra Modi said before the parade.

The fanfare also featured Indian air defence systems -- including missiles and drones -- that were deployed in the four-day conflict with arch-enemy Pakistan last year.

European Council President Antonio Costa and European Commission President Ursula von der Leyen are both in attendance, before an EU-India summit Tuesday, when the two sides are widely expected to announce a landmark free trade deal and security partnership.

They had been working on a trade agreement for over a decade before US President Donald Trump's trade tariffs pushed India and the 27-nation EU to expedite their efforts last year.

Republic Day marks the adoption of India's post-independence constitution in 1950 with the parade staged along a colonial-era boulevard that also hosts important government buildings.

The annual show is a colourful and tightly choreographed spectacle that also features floats from different Indian states to highlight the diversity of the country's 1.4 billion people.

India is on track to become the world's fourth-largest economy this year, according to International Monetary Fund projections.

Bilateral India-EU trade in goods reached 120 billion euros ($139 billion) in 2024, an increase of nearly 90 percent over the past decade, according to EU figures, with a further 60 billion euros ($69 billion) in trade in services.

The pact would be a major win for Brussels and New Delhi as both seek to open up new markets to counter US tariffs and Chinese export controls.

While the EU sees India as an important market, New Delhi sees Brussels as an important source of much-needed technology and investments to rapidly upscale its infrastructure and create millions of new jobs for its people.