Italian energy company Eni and its partners at Rockhopper Exploration said Monday they were among the first to win licenses for work off the coast of Croatia.

Rockhopper Chief Executive Sam Moody said in a statement he was pleased to partner with a company like Eni, which has a legacy of operations in Croatia reaching back to the 1980s.

"This represents an outstanding low cost opportunity to increase our acreage position in an area with proven hydrocarbons," he said.

Croatia has an estimated 71 million barrels of proven oil reserves, producing around 11,900 barrels of oil per day as of 2013. Natural gas reserves are estimated at 800 billion cubic feet, with production at around 65 billion cubic feet per day.

Eni said it's the leading producer in Croatia, with equity production of around 39 million cubic feet of gas per day.

Croatia offered companies the rights to explore for reserves using production sharing contracts with a five-year exploration phase and a 25-year production phase. When announcing the terms of the auction last year, the government said the company has an established production record, through much of the offshore sector remains highly under explored.

The government touts access to an oil pipeline system near the European market and plans for a liquefied natural gas terminal, which it said will establish the country as a key energy hub for the region.