The remarks come as the US confirmed a fifth round of strikes on Iranian-backed Houthis in Yemen.
US President Joe Biden has said that attacks on the Houthis will continue even as he acknowledged that the group have not stopped their Red Sea attacks.
The US carried out a fifth round of strikes on Yemen on Thursday after a US ship was struck by a Houthi drone.
White House spokesman John Kirby told reporters that US forces "took out a range of Houthi missiles" that were about to be fired towards the Red Sea.
He said the American attacks took place on Wednesday and again on Thursday.
On Wednesday, a Houthi drone hit a "US owned and operated bulk carrier ship" which later had to be rescued by India's navy. It came as the US designated the Houthis as a terrorist organisation.
"Well, when you say working are they stopping the Houthis? No," Mr Biden told reporters in Washington DC on Thursday before he left for a speech in North Carolina.
Not sure there was anything else going to happen about this. Houthis are shooting missiles so now they get missiles shot back in the hopes they'll stop.
Yeah, it's just that simple. /s. The absolute maximum leverage the US has (short of threatening invasion) would be to withdraw aid. We could certainly do that, but China and/or Russia would be more than happy to take on the job. Do you figure that would be helpful to the Palestinians? These dumb shit takes on foreign policy drive me nuts.