(CNN) Social activists Gaia Parisi and Matilde Rizzo are just friends -- but when Italy's ultra-conservative Interior Minister Matteo Salvini visited their hometown, the 19-year-olds couldn't resist the chance to photobomb him with a same-sex kiss.

Salvini, who is leader of the far-right, anti-immigrant League Party, recently endorsed and addressed an anti-LGBT and anti-abortion World Congress of Families event in Verona , Italy. The group's stated mission is to "defend the natural family."

(Ours is) ... a message of love and tolerance against the language and the attitude of hatred that politicians like Matteo Salvini keep spreading," Parisi told CNN. "But also it's an encouragement not to give up, to keep protesting against discrimination and injustices, because even a simple and natural act like a kiss can open a political debate."

Salvini recently caused outrage by snubbing Italy's annual Liberation Day, which celebrates the end of fascism and Nazism, in favor of promoting a local candidate in Sicily and speaking against the mafia.

The two teenagers were taking part in a protest in Caltanissetta, Sicily, where Salvini was speaking this week when he started posing for selfies with supporters. They walked over, queued for a few minutes, and when it was their turn, they kissed. Security immediately separated them. Salvini said he wished the pair well, and that they "have sons," and patted Rizzo on the head, Parisi said.

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