Moves by U.S. energy company Hess Corp. to streamline its portfolio leave it with few ways to diversify in the weak oil economy, Fitch Ratings said.

Fitch Ratings said it maintained the rating level for Hess at BBB, but revised its outlook from stable to negative. The ratings agency said it was basing its decision on the loss of diversification options that resulted from sales in the downstream, or refining, sector and the reduction in size of the company's upstream, or production, footprint.

"The negative outlook is driven by projected outspending on growth projects in 2016 that Fitch anticipates is likely to meaningfully reduce the company's liquidity under a lower for longer oil price scenario," it said in its ratings profile.

Hess reported a net loss of $279 million for the third quarter of the year as crude oil prices continued their steady decline. The upstream sector accounted for the bulk of the losses in the third quarter.

The company started 2014 by cutting its overall capital and exploration budget by 16 percent to $4.7 billion. Spending in the Bakken reserve area in North Dakota, a shale basin at the heart of the U.S. oil boom, was cut by 18 percent to $1.8 billion.

In July, Hess completed the sale of half of its midstream holdings in the Bakken reserve area of North Dakota to Global Infrastructure Partners for cash consideration of $2.68 billion. It sold its entire retail sector of gasoline stations and convenience stores to Marathon Petroleum Corp. in 2014.

According to Fitch, the company has sold off roughly $9 billion in assets since 2009. This "may limit its ability to liquidate additional assets under a lower-for-longer scenario without unfavorably impacting core credit metrics," the agency said.

Hess scheduled an earnings call Jan. 27 to discuss fourth quarter 2015 results.