Israel's Defence Minister Israel Katz has warned that the country would resume its war in Gaza if Hamas fails to uphold the ceasefire agreement and release Israeli hostages by Saturday.
"The new Gaza war will be different in intensity from the one before the ceasefire, and it will not end without the defeat of Hamas and the release of all the hostages.
"It will also allow the realisation of US President (Donald) Trump's vision for Gaza," Mr Katz said, referring to US President Donald Trump's plan for the US to take over the Palestinian territory.
His comments come as a Hamas delegation is in Cairo for Gaza truce talks, the group said, rejecting "American and Israeli threats" and demanding that Israel comply with the ceasefire deal.
The truce which came into effect last month largely halted more than 15 months of war, but has come under increasing strain in recent days, prompting a new push by mediators Qatar and Egypt to salvage it.
"A delegation headed by Khalil al-Hayya, head of the Hamas movement in the Gaza Strip, arrived in Cairo and began meetings with Egyptian officials," the Palestinian group said in a statement.
It added that the delegation, led by Hamas's chief negotiator, is monitoring "the implementation of the ceasefire agreement".
A senior Hamas official told AFP the delegation "will discuss ways to end the current crisis and ensure the (Israeli) occupation's commitment to implementing the agreement".
Yesterday, Israel warned that it could resume fighting if hostages are not released by Saturday, echoing a threat by US President Donald Trump who said "hell" would break out if Hamas failed to release "all" Israeli hostages by that day.
A sixth hostage-prisoner exchange under the truce deal was scheduled for Saturday, but earlier this week Hamas had announced it was postponing the upcoming release, citing Israel's failure to allow the entry of key humanitarian aid into Gaza.
A diplomat familiar with the talks said that mediators were engaged with both Israel and Hamas to resolve the dispute and ensure the implementation of the long-elusive agreement.
"Mediators are engaging with both Israel and Hamas to try to solve the current issues and ensure both parties of the conflict adhere to the ceasefire and hostage release agreement in place," the diplomat told AFP on condition of anonymity.
Hamas spokesman Hazem Qassem said the group demanded that Israel "adhere to the agreed humanitarian protocol".
"The Israeli occupation is evading the implementation of several provisions of the ceasefire agreement," Mr Qassem said in a separate statement.
"Our position is clear, and we will not accept the language of American and Israeli threats. Israel must commit to implementing the terms of the ceasefire agreement" to secure the release of its hostages, he said.
The spokesman added that talks with mediators were ongoing to ensure the agreement's implementation.
"We have received assurances from mediators that efforts are being made to compel the occupation to uphold the ceasefire terms in Gaza," said Mr Qassem.
A Palestinian source familiar with the issue earlier told AFP that mediators Egypt and Qatar were "working intensively" to resolve the crisis surrounding the ceasefire deal.
Qatar, Egypt 'working intensively' to resolve Gaza crisis
Qatar and Egypt are said to be "working intensively" to quell the crisis around the ceasefire agreement.
"Mediators from Qatar and Egypt are in contact with the American side," according to a Palestinian source.
"They are working intensively to resolve the crisis and compel Israel to implement the humanitarian protocol in the ceasefire agreement and begin negotiations for the second phase," the source added.
Earlier, Egypt's foreign ministry said it plans to "present a comprehensive vision for the reconstruction" of Gaza that ensures Palestinians remain on their land.
The statement came a day after US President Donald Trump said he could "conceivably" halt aid to Egypt and Jordan if they refuse to cooperate with his plan to take over Gaza and displace its population to their countries.
The Egyptian foreign ministry said it "hopes to cooperate" with Mr Trump's administration on the matter, with the goal of "reaching a fair settlement of the Palestinian cause".
It said its plan would provide for the reconstruction of Gaza "in a clear and decisive manner that ensures the Palestinian people stay on their land, and in line with the legitimate and legal rights of this people".
Hamas praised Egypt and Jordan for "rejecting displacement" plans for more than two million Gazans.
The group said that it "appreciates the positions of our brothers in Jordan and Egypt in rejecting displacement of our people and affirming that there is an Arab plan to rebuild Gaza without displacing its residents".
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Israel vows 'intense fighting' if hostages not released
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The ceasefire agreement was brokered by Qatar, Egypt and the United States after months of efforts under the administration of former US president Joe Biden.
As part of the first stage of the deal, the two warring sides were to begin indirect negotiations for the second stage 16 days after the first phase came into effect on 19 January.
Until now, these negotiations have not started, although there have been five hostage-prisoner swaps as agreed.
Hamas has released 16 Israelis in these five swaps, while Israel freed hundreds of Palestinian prisoners.
The sixth exchange is scheduled for Saturday, but earlier this week, Hamas announced it was postponing the upcoming release of hostages, citing Israel's failure to allow the entry of key humanitarian aid into Gaza.
Since then, tensions have only spiralled further.
"Things are still difficult and becoming more complicated," a Hamas source said.
"Israel's continued obstruction and failure to commit to starting the second-phase negotiations confirm the occupation's persistence in obstruction to sabotage the ceasefire agreement and resume the aggression, as there is nothing deterring the occupation."
