Citigroup reported a hefty decline in first quarter earnings Friday due to weak trading revenues and the energy bust in results that still bested analyst expectations.

Net income for the first quarter dropped 26.6 percent to $3.5 billion.

Revenues were down 11.4 percent to $17.6 billion.

Citigroup became the latest large US bank to set aside more funds for bad or vulnerable energy loans, as it boosted reserves by $233 million.

Results were also marred by a 27 percent drop in investment banking revenue and lower revenues from several key trading divisions, including equity markets and fixed income markets.

But Citigroup benefited from about a $360 million reduction in expenses and from increases in lending to core clients.

"While our market-sensitive products clearly suffered from weak investor sentiment during the quarter, we continued to make progress in several key areas," said Citigroup chief executive Michael Corbat.

Earnings translated into $1.10 per share, seven cents better than analyst expectations.

Citigroup shares rose 2.3 percent in pre-market trading to $46.00.