The announcement follows reports by Sky News over the weekend that Chanmugam, who has held the role since 2008, plans to step down later this year.
"BT confirms that a search process has commenced to find a successor but that no formal decision has been taken on a replacement or around the potential timing of any change. BT will make a further announcement if and when required," said the company.
Previously CFO of BT Retail, Chanmugan was promoted to his present role in 2008 following Hanif Lalani’s appointment to CEO of BT Global Services.
BT posted third quarter revenue growth of 3% year-on-year, generating £4.59 billion. Its EBITDA increased by 3% to £1.61 billion.
