Hamas is preventing Americans from leaving Gaza and entering Egypt, the White House said Sunday.

Egypt has agreed to allow U.S. citizens to pass through the cross at Rafah on Gaza's southern border, but Hamas terrorists turned away a group of Americans on Saturday. The State Department said 600 Americans are still in Gaza.

National security adviser Jake Sullivan told CNN on Sunday that the U.S. has told Egyptian President Abdel Fattah el-Sisi "to open the border to let Americans out."

"The situation there at the crossing is actually more complicated," he said, adding that it "was actually Hamas taking steps to try to stop that from happening."

Sullivan added that Secretary of State Antony Blinken was in Egypt on Sunday meeting with el-Sisi "to help get those American citizens out of Gaza."

It's unclear to what degree the Rafah crossing is even operational; Israel's shelling rendered the crossing "inoperable" on the Gaza side, the Egyptian foreign minister said Saturday. Further, Egypt reportedly closed the crossing to prevent the throngs of Palestinians who are looking to flee Gaza, a claim Egypt denied.

These reports cloud Sullivan's assertions that the cross is operable on the Gaza side but guarded by Hamas.

"Anyone who is a U.S. citizen should have the right to free passage through there, and then have the U.S. government facilitate their travel home," he said.

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