Luke Johnson is under pressure to give up control of an internal investigation into a £40m hole in Patisserie Valerie’s accounts over concerns that the review is not sufficiently independent.

The Times reports that Invesco, a top ten shareholder in the Aim-listed company, has told Mr Johnson and the board of Patisserie Holdings, the parent company, to hand over the investigation to a law firm or an independent investigation firm during talks last week, according to people familiar with the matter.

Invesco has also approached the Investor Forum, an influential group that brokers meetings between large shareholders and company executives, about its worries and could explore legal action to force the board to cede control of the investigation.

A person close to Invesco told The Times: “Shareholders are concerned the board has given itself supervision of the investigation into [its] own conduct and potential incompetence.”

Directors of Patisserie Valerie launched an investigation into “significant, potentially fraudulent accounting irregularities” on October 10 after the discovery of a black hole in its finances.

Patisserie Valerie told investors ten days ago that its investigations “remain at a very preliminary stage” and could last for months. It said the directors “cannot predict the outcome of those investigations with any degree of certainty” and warned that any further findings could result in material losses for shareholders.