Vodafone Spain was the subject of takeover interest, with Bloomberg reporting the operator had been approached by private equity and strategic suitors regarding a possible deal worth more than $4 billion.
Bloomberg sources stated Vodafone Group would consider a sale at the right price, but it is not actively running a formal process at the present time.
Sources did not name companies which had expressed an interest, but stated deliberations are ongoing.
The news comes a day after the European Commission opened a detailed investigation into another proposed major merger in the Spanish market, which would see Orange and Masmovil tie-up if the deal is cleared by regulators.
In 2019, Vodafone was also linked with a deal with Masmovil and Bloomberg added former group CEO Nick Read was interested in a merger in 2022, only to miss out to Orange.
Under interim CEO Margherita Della Valle, Vodafone Spain has somewhat been relegated from main market status after being folded into a group of smaller units along with the Republic of Ireland and Greece.
The Spanish unit had also been subject to several rounds of cuts over recent years.
To add to uncertainty, Vodafone Spain CEO Colman Deegan departed in March, and was replaced by the head of its Portuguese unit from 1 April.
At group level, Vodafone is under pressure from investors to simplify its business by offloading smaller units and revive its share price.