The clothing brand behind the ‘Gay is O.K’ range, as well a host of LGBT friendly advertising campaigns, has filed for bankruptcy.

The owners of the company – which has been hit by falling sales, high debts and ongoing management crises – today announced a deal to “restructure its finances”.

American Apparel is well known for its continued support of the LGBT community and has ran various campaigns in a bid to promote equality.

The brand’s ‘Legalise Gay’ and ‘Gay is O.K’ clothing ranges have regularly been worn by LGBT campaigners worldwide – including a clothing line which challenged the anti-gay laws of Russia prior to the 2014 Sochi Winter Olympics.

The company is also known for handing out over 50,000 free pro-gay t-shirts during Pride parades across the planet and running ads featuring same-sex couples kissing and holding hands.

In addition, their campaigns have often featured celebrities from LGBT culture – including RuPaul royalty, American Apparel Ad girls Willam, Alaska and Courtney Act and viral sensation Brendan Jordan.

“American Apparel believes that sexuality should be celebrated, not condemned,” the company’s website reads.

“American Apparel believes in freedom, expression and equality, things that are inherently condemned in the prohibition of gay marriage.

“With many of our employees and customers identifying as gay, lesbian, bisexual or transgender, we are a company that is vocal about our support for the protection of gay rights.”

American Apparel was founded in 1989 by Dov Charney.

However, the firm fired him in last year over misconduct claims and Mr Charney is suing the company for defamation and fraud.

The combination of the firm’s debts, falling sales and management crises have “finally proven too much for the iconic teen retailer”, said Neil Saunders of retail analysis firm Conlumino.

“Bankruptcy protection is, in our view, the only viable option for American Apparel which is crippled by $311m of debt and is subject to a number of corporate lawsuits, including those brought by its founder Dov Charney,” he said.

“Arguably, the big loser will be Dov Charney, who will not only see his legal proceedings delayed but will also find, along with other shareholders, his holding in the company – currently worth some $8.2m – wiped out,” he added.

It currently has 18 stores and concessions in the UK including locations in London, Leeds, Glasgow, Manchester and Brighton.

The company has yet to release details of any closures of its stores.