Israeli centrist opposition leader Yair Lapid said Saturday that "antisemitism" is the only "rational explanation" for UN Secretary-General Antonio Guterres' decision to call for a humanitarian cease-fire in Gaza.

Guterres used Article 99 of the UN Charter to force the Security Council to debate a resolution calling for a halt to the fighting. The United States, however, blocked the resolution.

"The UN Secretary General hasn't invoked Article 99 for decades," Lapid's series of social media posts began. "Not when half a million were killed in Syria, over 4 million killed in Congo, 450,000 where butchered in Darfur or when tens of thousands were killed and millions have fled Ukraine."

"Only when Israel defends itself after our children were murdered by brutal terrorists and our people were taken hostage, does the UN Secretary General suddenly decide to invoke Article 99 to help Hamas," Lapid wrote.

"How do we know its [sic] antisemitism? Because there is no other rational explanation."