Borrell recalled that U.S. President Joe Biden said last week that Israel's response to the Oct. 7 Hamas attack had been "over the top" and U.S. officials had repeatedly said that too many civilians were being killed in Gaza.

"Well, if you believe that too many people are being killed, maybe you should provide less arms in order to prevent so many people being killed," Borrell told reporters after a meeting of EU development aid ministers in Brussels.

"If the international community believes that this is a slaughter, that too many people are being killed, maybe we have to think about the provision of arms," he added.

(Reporting by Andrew Gray, writing by Andrew Gray and Julia Payne, Editing by Charlotte Van Campenhout)