The spokesman for the United Nations secretary-general on Monday pitched into the sexism row engulfing Spain, asking: "How difficult is it not to kiss somebody on the lips?"

Stephane Dujarric, spokesman for UN chief Antonio Guterres, called on authorities to address sexism "in a manner that respects the rights of all female athletes" after the Spanish football chief's forcible kiss on the lips of World Cup player Jenni Hermoso.

"There is a critical issue of sexism that remains in sports," he said.

Luis Rubiales grabbed Hermoso by the head and kissed her lips in front of millions of people as he congratulated the Spanish team on winning the World Cup on August 20.

Hermoso has described the kiss, which has sparked a global wave of indignation, as "an impulsive, macho act, out of place and with no type of consent on my part."

Rubiales has insisted it was consensual and refused to resign his post.

Prosecutors at Spain's top criminal court said Monday they had opened a preliminary sexual abuse investigation into the incident.

Rubiales, who was provisionally suspended from his post as president of the Spanish Football Federation (RFEF) by Fifa on Saturday, could face an extended sanction if the country's sports court accepts complaints against him in a meeting on Monday.