The leader of Hamas in the Gaza Strip, Yahya Sinwar, said Wednesday that talks were underway on reaching a cease-fire deal with Israel, while issuing a threat that "all of the missiles that the Palestinian resistance fired [at Israel] during the 51 days of the last war [in 2014] it can fire in five minutes."

Hamas, he warned, had sent a message to Israel through intermediaries that it is capable of "causing six months of rising and falling air raid sirens" in the Tel Aviv area. "We don't want a military confrontation, but we are not afraid of one."

About the negotiations with Israel via Egyptian and UN mediation, Sinwar said it was possible to make progress in talks on the return of two Israeli civilians being held in Gaza and the remains of two Israeli soldiers killed in combat there in 2014, in exchange for Palestinian prisoners. As reported by the Ma'an Palestinian news agency, Sinwar said the issue was not linked to contacts with Israel on a long-term cease-fire.

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Speaking to reporters, Sinwar said such a cease-fire agreement could be reached with Israel even in the absence of reconciliation between the West Bank-based Palestinian Authority and Hamas, which controls the Strip. He said that Egypt has expressed a willingness to pursue such a deal.

As for reconciliation between Hamas and Fatah, Sinwar said Fatah had responded on Wednesday to an Egyptian proposal and that the response was "worse than their initial proposal." Commenting on the prospect that the Palestinian Authority might impose sanctions on Gaza if there is no progress on Palestinian reconciliation, Sinwar said: "That would be a break with the rules of the game and we would respond accordingly."

Late on Wednesday, the White House took the Palestinian Authority to task for its refusal to be involved in efforts to reach an agreement on restoring calm to Gaza. The statement and its timing - shortly after Egyptian President Abdel-Fattah al-Sissi had spoken to Palestinian Authority President Mahmoud Abbas about Gaza - are indications that the Trump administration and Egypt are attempting to ratchet up the pressure on Abbas to support an agreement and to have the Palestinian Authority gradually reassume responsibility for the Strip.

Hamas forcibly took control of Gaza from the Palestinian Authority in 2007 after Fatah lost parliamentary elections three year before.

In the statement, Trump's special Middle East envoy, Jason Greenblatt, said: "The Palestinian Authority cannot criticize from the sidelines. The Palestinian Authority should be part of the solution for the Palestinians of Gaza and Palestinians as a whole. If not, others will fill that void." He added that "it's time for the Palestinian Authority to lead the Palestinian people – all Palestinians – to a better future."

Up to now, Abbas has voiced skepticism over talks under Egyptian mediation on Gaza. One of the reasons for Abbas' approach is concern that the talks would strengthen Hamas at the Palestinian Authority's expense.

On Wednesday, remarks about Gaza made by the U.S. ambassador to Israel, David Friedman, were leaked to the press. In a telephone briefing to the American Jewish Congress, Friedman said an agreement on Gaza without the Palestinian would be a "tremendous reward" for Hamas. Despite the Palestinian Authority's many shortcomings, the Trump administration prefers to work with the Palestinian Authority rather than Hamas, Friedman added.