A 10% stake in the operator is currently valued at around US$2.20 billion.
In September it was announced that the Saudi-based group would purchase a 9.9% stake in Telefónica for around $2.1 billion, through an acquisition of shares and financial instruments.
The partnership, which began as a strategic agreement that was signed in February, has steadily developed throughout the year.
stc has insisted that it does not intend to acquire a majority stake in Telefónica and has labelled the move as a “compelling investment opportunity” according to Olayan Alwetaid, CEO of the company.
The aim of the Spanish stake is to give Telefónica “shareholding stability”, according to a filing made by the government holding company that will buy the shares.
Capacity reported the Spanish fund was interest in acquiring the company in November.
The move is a partial renationalisation of Telefónica, which has operated as a private company since 1997.
Earlier this month, it was reported that Telefónica would slash its workforce by up to 25% in Spain.
The cuts are part of the company's three-year strategic plan to boost profitability by reducing capital expenditure, raising revenue and cutting costs.