File photo: Chinese Foreign Ministry Spokeswoman Mao Ning. AP
Washington's decision to supply the munitions as part of a new military aid package drew "widespread attention from the international community, with many countries expressing opposition", Chinese foreign ministry spokeswoman Mao Ning said.
But she stopped short of condemning the approval outright, instead noting that "the irresponsible transfer of cluster munitions can lead to humanitarian problems".
"We should fairly manage humanitarian concerns and legitimate military and security needs, and maintain a prudent and restrained attitude towards the transfer of cluster munitions," she added.
Humanitarian groups have strongly condemned the US decision to supply cluster munitions, which are banned across a large part of the world and can go undetonated, potentially endangering civilians for years to come.
Neither China nor the United States are signatories to the Convention on Cluster Munitions, which prohibits the use of the weapons.
Russia also has not signed the treaty, and its own use of cluster bombs in Ukraine has drawn criticism.
While China says it is a neutral party in the Ukraine conflict, it has been criticised for refusing to condemn Moscow for its offensive.