LISBON (Reuters) – Portugal’s Sonae has moved to strengthen its position in local telecoms firm NOS by increasing its stake and ditching a partnership with Isabel dos Santos, the daughter of Angola’s long-time former president.

Sonaecom, part of the Sonae conglomerate, said in a filing late Wednesday it had dissolved ZOPT, a 50-50 venture with dos Santos that had held a controlling 52.15% stake in NOS.

Dos Santos was named a suspect in a fraud investigation in Angola in January and her shares in NOS were seized by a Lisbon court in April, depriving ZOPT as a whole of its voting rights.

Dos Santos has repeatedly denied wrongdoing.

ZOPT’s assets, including its shares in NOS, will be equally divided between its shareholders, Sonaecom said in the filing with Portugal’s market regulator CMVM.

Sonae said it in a separate statement it had bought 7.38% of NOS shares from private bank BPI, and was now the telecom operator’s largest shareholder with a 33.45% stake.

Sonaecom had said in April it would contest the decision to deprive ZOPT of its voting rights, saying it was “not liable for the debts of its shareholders”.

Dos Santos has sold or been stripped of nearly all her stakes in major Portuguese firms, with her indirect stake in oil firm Galp now the only one left unscathed by the scandal.

Dos Santos had no immediate comment.

The investigation into her relates to alleged mismanagement and misappropriation of funds during her time as chairwoman of state-owned Angolan oil company Sonangol.

Portugal’s public prosecutor ordered the seizure of her Portuguese bank accounts in February.

In December, Angola froze her stakes in Angolan firms including Unitel, BFA and ZAP MIDIA.