Chilean state oil company ENAP has signed a deal with ConocoPhillips (NYSE: COP) to explore and eventually exploit gas deposits in the nation's remote southern Magallanes region, a source familiar with the agreement confirmed on June 13.

Local newspaper El Mercurio first reported the deal in which ENAP will retain a 51% stake in the project. A source speaking to Reuters on condition of anonymity confirmed the agreement.

The project will be rolled out in phases depending on the success of each stage, with ConocoPhillips possibly investing between $70 million and $100 million over the next four years, according to the paper.

ENAP's CEO, Marcelo Tokman, told Chile's La Tercera newspaper earlier in June that it was planning to solicit outside funding in 2016 to fund an ambitious $800 million investment plan, which included gas exploration in Magallanes.

ENAP, Chile's main oil refiner and a key provider of fuel to the domestic market, produces little crude oil but has invested heavily in gas exploration in the southern part of the country.