US far-right activist and Donald Trump loyalist Laura Loomer launched a blistering attack on New York City Mayor Zohran Mamdani on Wednesday after he called Israeli Prime Minister Benjamin Netanyahu a “war criminal” and said he is “not welcome in New York City.”Loomer, who is Jewish, called for a ban on Muslims holding public office in the United States and urged President Donald Trump to reinstate the “Muslim ban.”“Ban Muslims from holding office in America,” Loomer said.Appealing directly to the MAGA supremo, he wrote: “We will never make America safe again until President Trump goes back to enforcing his Muslim ban. This time, make it the Muslim ban it was intended to be. No Islamic travel ban.”Addressing X, Loomer accused Mamdani of being sympathetic to Iran and Hamas, and claimed without providing evidence that he posed a national security threat. “When you allow Muslims to participate in the American political system, you get Twelver Shia supporters of the Iran regime and Hamas lovers like Mamdani ruling America’s largest city. This will not end well.”He further claimed that Mamdani would never receive an FBI security clearance, saying, “I’m pleased to have the Trump administration confirm to me that Mamdani will never be granted an FBI security clearance.” Quoting an unnamed source, Loomer wrote, “My senior FBI source told me, ‘Senior FBI leadership has reason to believe that Mamdani may have direct communications with Islamic terrorist organizations. He certainly poses a threat to national security, which is why we refused to give him an FBI-approved security clearance.’ He won’t get even one.”Loomer continued, “I had stressed this point even before Mamdani was elected,” and further claimed, “Shockingly, my FBI source confirmed to me that they reportedly have reason to believe that Mamdani has direct communications with terrorist organizations.”The comments came as Mamdani stepped up his criticism of Netanyahu in a video posted on Twitter on Tuesday, saying the Israeli leader is “not welcome in New York City” and urging the US federal government to enforce the International Criminal Court (ICC) arrest warrant against him.Calling Netanyahu a “war criminal”, Mamdani accused him of committing atrocities during Israel’s military campaign in Gaza.“He is a war criminal, the architect of a terrible genocide against the Palestinian people,” Mamdani said.He further accused Netanyahu of being “responsible for maiming thousands of children as those who survive are subjected to amputations without anesthesia. For targeting neonatal hospitals and maternity care centers, for not even giving newborns a chance to live. He starved countless people as he blocked food and humanitarian aid from reaching them.”Referring to the ICC arrest warrant, Mamdani said: “There is a reason why the International Criminal Court issued a warrant for his arrest. As I have said, I agree with the ICC that Benjamin Netanyahu should be arrested and prosecuted for his crimes as I do for anyone else charged by the ICC.”