An accounting scandal involving massive Japanese conglomerate Toshiba deepened on Saturday as reports said the company's president would likely be forced to resign.

The resignation of Toshiba President Hisao Tanaka will befinalisedafter a third-party panel tasked with investigating the scandal releases its report as early as next week, the Kyodo news agency said, citing unnamed sources.

The Japanese firm, which makes everything from batteries to nuclear reactors,has allegedly overstatedaround 200 billion yen ($1.6 billion) in its group operating profits for the five years to March 2014, Kyodo and Jiji Press said.

The accounting irregularities are believed to have affected its mainstay infrastructure-related, semiconductor, television and personal computer businesses.

Tanaka and former president and current Vice Chairman Norio Sasaki are among those behind the profit-padding, the reports said, as they allegedly put excessive pressure on subordinates to achieve profit targets.

Sasaki, who served as Toshiba president between June 2009 and June 2013 -- covering most of the period during which the company allegedly padded its profits -- will also resign over the scandal, Japanese media have said.

Toshiba has said it was revoking its earnings forecast -- a 120 billion yen net profit on sales of 6.7 trillion yen -- for the past fiscal year and would not pay a dividend.