A trade union has accused craft beer giants, BrewDog, of ignoring its attempts to engage in discussions about workers' concerns after former employees of the company signed a letter claiming there were “toxic” attitudes at the firm.

Last month, one of BrewDog’s founders and chief executive James Watt issued an apology which acknowledged the detrimental impact that some practices had on employees.

On Tuesday, Mr Watt shared a progress report of the review of the company culture which was announced on June 17.

READ MORE: BrewDog boss apologises after ex-employees write open letter criticising workplace

However, in response Unite Hospitality claimed that contact to both Mr Watt and BrewDog president David McDowall 11 days ago seeking ‘discussions ensuring workers have a collective voice to resolve the serious issues which remain’ have not been responded to. 

Unite Hospitality tweeted: "11 days ago, we wrote to @BrewDogJames & @BrewDogDave seeking discussions about ensuring @BrewDog workers have a collective voice to resolve the serious issues which remain.

"They haven't even bothered to respond."

In June, 61 former staff members and 45 who did not include their names or initials, claimed workers experienced a “residual feeling of fear” during their time at the Ellon-based beer company.

READ MORE: BrewDog: boss cancels Aberdeen TED talk after toxic work culture claims

The lengthy letter from “Punks With Purpose” alleged that a “significant number of people have admitted they have suffered mental illness as a result of working at BrewDog”.

“It doesn’t matter which part of the business we worked in; production, bartending, sales, operations, packaging, quality, marketing or HR, we all felt that in our day to day working lives, there were at best hurdles, and at worst genuine safety concerns,” it said.

Almost 4,000 individuals have signed a petition created by Unite Hospitality trade union organiser Bryan Simpson to give workers a “real voice” through “collective recognition”.

A spokesperson for BrewDog said: “We are totally committed to delivering on our action plan for our people.

"Feedback on the many actions set out so far has been very positive. This is what we are focused on right now.”