Former Fujitsu president Kuniaki Nozoe has revealed he was forced to leave the firm in September owing to connections with an unnamed business of " unfavourable reputation".

As a result, shares in the company have plunged by 2.7 per cent.

Fujitsu had originally said that Nozoe’s departure from Fujitsu after 15 months in the job was due to illness.

Despite the alleged wrongdoing, Nozoe wanted to annul his resignation and, in response, the company put out a statement outlining the reasons behind its decision to sack him.

The IT giant had kept its former president as an adviser, but dismissed him from the role over the weekend.

Fujitsu asked for ‘understanding’ from its shareholders as to why it had not released the full facts behind Nozoe’s departure.

It added that while his actions were not illegal, the association with the third-party had put Fujitsu at risk.