The administration of U.S. President Joe Biden is closely monitoring the probe into a deadly Israeli airstrike it called tragic, but it said on Tuesday the recent deaths in Rafah didn't constitute a major ground operation there that crosses any U.S. red lines.

"The Israelis have said this is a tragic mistake," National Security Council spokesperson John Kirby told reporters at the White House, when asked about whether the events over the weekend qualified as the type of "death and destruction" U.S. officials have warned could result in the withholding of more aid to Israel.

The U.S. doesn't have "a measuring stick here or a quota," Kirby said.