"Our Israeli allies announced overnight that they are shifting from retaking their territory to an offensive. The United States must ensure that Israel has all the weapons and all the time that it needs to utterly eradicate Hamas, and we must be unambiguous about that commitment," Cruz went on to say.
"Instead, this weekend the State Department repeatedly posted statements and summaries calling for premature ceasefires and for Israel to stand down, while other times Biden administration officials said they were not pressuring Israel."
"This ambiguity badly undermines our ally’s campaign against the Iran-controlled terrorists in the Gaza Strip, endangering the safety and security of Israelis and Americans," he said.
The State Department said at least nine Americans have been killed by Hamas' strikes on Israel, Fox News has confirmed.
Israeli media also is reporting that at least 800 Israelis have died since Saturday, when the group first began launching terrorist attacks on the country.
The White House has confirmed at least 11 American citizens were killed in the carnage.
The administration has yet to release the names of those Americans, and it has acknowledged the possibility that there are more U.S. citizens being held hostage in Gaza.
Biden spoke on the phone with Israeli Prime Minister Benjamin Netanyahu earlier Monday. The president's Israeli counterpart warned that a ground invasion of Gaza may be imminent.
Fox News Digital's Greg Norman and Anders Hagstrom contributed to this report.