Sara Lee, the US food group, is planning to split the roles of chairman and CEO in the future - but is refusing to be drawn on whether investor pressure prompted the move.

The company behind Ball Park Franks and Jimmy Dean sausages has decided to appoint a separate chairman when current chairman and CEO Brenda Barnes steps down from the two roles.

A report in the Financial Times last week claimed that pension fund Norges Bank Investment Management had put pressure on Sara Lee to hire an independent chairman when Barnes' time at the helm ends.

However, a spokesman for Sara Lee refused to comment on the pension fund and said the change was in line with corporate policy at other companies - as well as proposed legislation going through the US Senate.

"When Brenda is no longer CEO - and we have no plans for that to happen and no timeline - we will then split the roles of chairman and CEO. Though many Fortune 500 companies have a dual chair/CEO, splitting the roles is the growing trend," the spokesman told just-food.

"There is proposed legislation, such as Senator Charles Schumer's Shareholder Bill of Rights Act that would, if passed, require all US public companies to appoint an independent chair."

The spokesman insisted that Sara Lee would not see a "significant change" in how the company's board functions when an independent chairman election due to the group's use of a lead independent director.