Lord Browne, the chief executive of BP, is facing a possible grilling by the US federal safety watchdog over last year's explosion at the oil giant's Texas refinery, which killed 15 people.
Don Holmstrom, the lead investigator at the Chemical Safety and Hazard Investigation Board (CSB), told The Independent on Sunday that it was "possible" Lord Browne would be interviewed. He said the CSB would decide in the next few weeks.
A spokesman for the CSB admitted that "it would not be typical" if Lord Browne was called to give evidence. "But this was not a typical accident," he added. "This was the worst workplace accident for 15 years. We are doing the most detailed and copious investigation."
BP's environmental and safety record has been tarnished by a string of recent incidents and ongoing investigations. Last week it emerged that the company had received a subpoena from a federal grand jury relating to its oil spill in Alaska in March. Should the grand jury decide to indict BP, it could result in fines and even prison sentences for some of its officials.
The CSB does not have the power to fine or prosecute companies. It will publish its investigation into the Texas accident, probably in November. Its remit is to identify where a company has breached safety practices and to recommend new guidelines where relevant to prevent future accidents.
Mr Holmstrom said the team from the CSB had already interviewed the head of BP's global refining division. "It's possible [that we will interview Lord Browne]," he added. "We have not made a decision. It depends on factors which may come from additional interviews. We want to know what improvements were made, what was done and not done."
The accident happened in March last year when a gas drum exploded and ripped into contractors' trailers nearby, killing 15 people and injuring 170. In September, BP was fined $21m (£11m) by US regulators.
In an initial report, the CSB said: "Many of the CSB team's findings are indicative of management culture issues at BP."
A spokesman for BP stated that "BP has fully co-operated with the CSB. We will continue to give serious consideration to future requests."