Spanish soccer star Jenni Hermoso has officially filed a criminal complaint against Luis Rubiales for planting a kiss on her following the country's World Cup victory last month claiming that the act was sexual assault.

Spain's football star Jenni Hermoso filed a criminal complaint over the unsolicited kiss by federation boss Luis Rubiales after Spain won the Women's World Cup, prosecutors said on Wednesday.

The complaint, which was filed on Tuesday, is key for a preliminary investigation, which prosecutors at Spain’s top criminal court have opened for the alleged crime of “sexual assault”, to move forward.

The lawsuit could entail criminal charges against Rubiales, in addition to ongoing investigations by Spain's top sports court into "serious misconduct" and an investigation by world football's governing body FIFA, which has provisionally suspended Rubiales.

With the complaint, Rubiales could face criminal charges in addition to the ongoing inquiry by Spain's top sport court for "serious misconduct" and an investigation by world soccer governing body FIFA, which has provisionally suspended Rubiales from office. 

Rubiales grabbed Hermoso's head and kissed her on the lips during the medal-giving ceremony that followed Spain's 1-0 victory over England in the Women's World Cup final on Aug. 20.

Hermoso later said the unwanted kiss had left her feeling "vulnerable and like the victim of an assault," with a statement on social media describing it as "an impulsive, macho act, out of place and with no type of consent on my part." 

Rubiales, who has so far refused to resign despite heavy pressure, said the kiss was "spontaneous, mutual, euphoric and consensual."

Late last month, the prosecutor for Spain's High Court said Rubiales could face a sexual assault charge, which can carry a prison term of between one and four years, if Hermoso were to file a complaint.

Hermoso now plays for Mexican club Pachuca after a long career with top Spanish and European clubs, including Barcelona, Paris Saint-Germain and Atletico Madrid.