Retired U.S. Army Ranger Sean Parnell said London Mayor Sadiq Khan is continuing to be irresponsible by not mentioning "radical Islamic terrorism."
"This is a guy who said terrorist attacks are part and parcel with living in a big city," Parnell said of Khan.
Parnell said there are more than 20,000 people in Britain who sympathize with jihadism, but that Khan continues to ask for discourse.
"We are well beyond the point of a conversation with the Muslim community. This is a counterinsurgency right now," Parnell said.
"Do you think the parents that had children killed during the Ariana Grande concert want to talk about a conversation?" he asked.
President Trump also criticized Khan's response to the second terrorist attack in his city in as many weeks.
At least 7 dead and 48 wounded in terror attack and Mayor of London says there is "no reason to be alarmed!"
— Donald J. Trump (@realDonaldTrump) June 4, 2017
Khan said in an interview that there is "no reason to be alarmed" and that he "will never let the terrorists win."
Trump was criticized in some quarters for his remark, since it was unclear in-context whether Khan was addressing the attack or London's now-elevated police presence.
We are all shocked and angry today - but this is our city. We will never let these cowards win and we will never be cowed by terrorism. pic.twitter.com/kcosumkdCR
— Sadiq Khan (@SadiqKhan) June 4, 2017
Khan said he was "furious" at the attackers, calling them "cowards" and saying London will "never be cowed by terrorism."
Watch the clip above.