Global investment management firm Pimco is adding energy-related securities to some of its portfolios as the Newport Beach, California firm expects oil prices to rise over the next 12 months, Dan Ivascyn, group chief investment officer, said in an interview on Tuesday.

"We've been adding some oil-related and energy-related names in our broader mandates," Ivascyn said. Pacific Investment Management Co, which is a unit of Allianz SE, oversaw $1.47 trillion in assets under management as of Sept. 30.

"We are becoming constructive in this sector because we expect oil higher in price over the next 12 months or so," Ivascyn added. He declined to provide any specific names Pimco is adding to some of its portfolios.

Ivascyn affirmed that the $52.4 billion Pimco Income Fund still holds a tiny exposure in Brazilian oil producer Petrobras. In the multi-sector bond category, Pimco Income is posting returns of 3.30 percent year-to-date and outperforming its category by 2.34 percentage points. It is surpassing 98 percent of its peer category.

On a 12-month basis, Pimco Income is posting returns of 2.63 percent, easily beating 97 percent of its peer category.

Monday, Pimco named two former central bank chiefs and a former British prime minister to sit on a new board to advise on economic, political and strategic developments.

Ben Bernanke, who chaired the U.S. Federal Reserve from 2006 to 2014 and was named a senior Pimco adviser in April, will lead the Pimco Global Advisory Board.

The board also includes Jean-Claude Trichet, president of the European Central Bank from 2003 to 2011, and Gordon Brown, the U.K. prime minister from 2007 to 2010.

Other members include Ng Kok Song, who was group chief investment officer of the Government of Singapore Investment Corp sovereign wealth fund from 2007 to 2013; and Anne-Marie Slaughter, president of the think tank New America and a former U.S. Department of State policy director.