(Reuters) - Buyout firm Apollo Global Management LLC is seeking to raise more than $4 billion (2.8 billion pounds) for its third natural resources-focused private equity fund, according to people familiar with the matter.

The fundraising effort comes as a recovery in energy prices drives private equity firms to raise cash to invest in the oil patch. Fourteen natural resources-focused private equity funds completed fundraising in the first quarter of 2018, raising a combined $13 billion, according to market research firm Preqin.

Apollo Chief Executive Leon Black told an industry conference last month that the New York-based firm expected to raise another private equity fund which would invest in natural resources this year, having invested around 80 percent of its predecessor fund, Apollo Natural Resources Partners II.

Investors in that second fund have been contacted about backing the latest fund, the sources said this week, asking not to be identified because the information is not public.

Apollo declined to comment.

Private equity firms have been big investors in the energy space in recent years, drawn by the prospect of making significant returns by scooping up cheap assets whose value were impacted by commodity prices falling from their mid-2014 peak.

Their capital has also been welcomed by an industry which is grappling with the high costs of exploration and development.

Apollo Natural Resources Partners II raised $3.5 billion in 2016. It had an internal rate of return, net of fees, of 31 percent as of the end of December, according to an Apollo regulatory disclosure.

Apollo Natural Resources Partners I, which raised $1.2 billion in 2012, had a net internal rate of return of 9 percent.

(Reporting by David French and Greg Roumeliotis in New York; Additional reporting by Joshua Franklin in New York; Editing by Cynthia Osterman)

By David French and Greg Roumeliotis