(Reuters) - Activist fund Crystal Amber more than doubled its stake in De La Rue Plc <DLAR.L>, days after the banknote printer warned of "significant doubt" that it can continue as a going concern and said it would scrap its dividend to tackle mounting debt.
Crystal Amber on Tuesday disclosed a stake of 14.33% as at Nov. 29, from an earlier stake of 7.12%, making the fund De La Rue's biggest investor.
De La Rue also reported a first-half loss last week as it tackles stiff competition, but Crystal Amber said at the time that it was "not alarmed" by the passport printer's weak results and would buy more shares.
Crystal Amber said then that the fund was "very encouraged" by De La Rue's new top boss Clive Vacher, who took over in October and has been tasked with turning around the company and reducing its debt burden.
De La Rue has suffered a series of setbacks, including two profit warnings, an investigation into suspected corruption in South Sudan and the loss of a 400 million pound contract for Britain's new passports.
The over 200-year old firm, which holds the contract to design and manufacture the Bank of England's new polymer notes, has said it would conduct a review of its business that will speed up its restructuring plan to cut overhead costs and focus on inventory management.
De La Rue shares were down 1.13% at 139.4 pence.
(Reporting by Noor Zainab Hussain in Bengaluru; Editing by Shounak Dasgupta)