"The US is going to continue to commit to the Ukrainian people to do everything that we can to make sure that they have the assistance on the ground to fight for their freedom," she told a press gaggle in Dublin, Ireland.
The spokeswoman was quizzed about whether the US and NATO were concerned that the Ukrainian conflict could escalate into one between NATO and Russia.
She said the allies showed a strong commitment to making sure that Ukrainians "get what they need when it comes to security assistance, making sure that they are able to fight on the ground."
Russia has repeatedly warned countries sending weapons to Ukraine that it sees military shipments as legitimate targets. Russian Foreign Minister Sergey Lavrov has said that NATO allies arming and training Ukrainians is tantamount to a direct involvement in the conflict.