Lindsey Graham, a Republican senator, has attempted to deride renowned activist Greta Thunberg for joining an effort led by the Freedom Flotilla Coalition (FFC) to break Israel’s naval siege on Gaza and deliver humanitarian aid, according to Al Jazeera.

“Hope Greta and her friends can swim,” the prominent legislator wrote on X.

The FFC’s previous attempt to break the Israeli siege was dealt a blow by drone attacks that breached their ship’s hull, and were believed by many to be carried out by Israel.

Responses to Graham’s post included users who asked, “Why would a US senator be threatening a young climate activist?” and, “Why is a 69-year-old US senator joking about the drowning of a 22-year-old Swedish activist? Is this where American politics is now?”

Thunberg, as well as Game of Thrones actor Liam Cunningham, are among those joining the mission, which set sail from Italy yesterday.