BP’s Chief Executive, Lord Browne, was not interested in safety issues at the oil company’s American plants, according to evidence to an internal investigation into the Texas City refinery explosion, in which 15 people died and 180 were seriously injured.

The internal investigation into the Texas City blast included copious notes taken during interviews with present and former BP executives who were responsible for operational, environmental and safety issues at BP’s North American refineries.

During one of the interviews, Greg Coleman, the former vice-president of BP’s health, safety and environmental programmes, said that Lord Browne “showed little interest” in safety. Mr Coleman added that the BP chief showed “no passion, no curiosity, no interest” in safety issues. Coleman has since left the company.

The notes, and the results of the internal investigation, were not meant to be made public, a BP insider said, as their contents could prove highly embarrassing to the oil company as it tries to recover from the series of set backs in the United States.

A spokesman for BP in London confirmed the authenticity of the documents, however, adding that they were highly confidential.

The revelation is another embarrassment for Lord Browne as BP tries to restore the image of its troubled North American operations after a series of safety and environmental disasters. He was once seen as the best businessman of his generation. But for how much longer?