UK oil group Burren Energy is buying more than a quarter of Indian firm Hindustan Oil Exploration for £13.8m.
India will become Burren's fourth area of operations
The purchase of a 26% stake in Gujarat-based Hindustan represents Burren's first corporate acquisition since its flotation in London in 2003.
Hindustan is India's only publicly quoted oil and gas explorer, and has a portfolio of onshore and offshore assets in its native country.
Burren said Hindustan was a chance to enter the Indian oil and gas industry.
The UK firm said it intended to make India the fourth leg of its business, adding to its existing interests in the Caspian Sea, and west and north Africa.
"This investment in Hindustan is very compelling for Burren," Burren chief executive Finian O'Sullivan said.