Israeli Prime Minister Benjamin Netanyahu warned Sunday that a ceasefire in Gaza, scheduled to begin at 0630 GMT, would not take effect unless Hamas provided a list of hostages to be released. The militant group said the delay was due to "technical reasons."

"The prime minister instructed the IDF (military) that the ceasefire, which is scheduled to take effect at 8:30 a.m., will not begin until Israel has received the list of released hostages, as Hamas has committed to providing," Netanyahu's office said in a statement.

Hamas said it was "affirming its commitment" to the terms of the ceasefire.

"The delay in providing the names of those to be released in the first batch is due to technical reasons," the group said in a statement.

Late Saturday, Netanyahu had warned that the swap of Palestinian prisoners for hostages on Sunday would not happen unless the list of captives was provided.

He also said that Israel reserved the right to resume the war "if necessary," with U.S. support, and that the current ceasefire was "temporary."

The ceasefire, set to begin at 0630 GMT, comes after months of difficult negotiations mediated by Qatar, Egypt, and the United States.