Hamas leader Ismail Haniyeh on Saturday accused Israel's Prime Minister Benjamin Netanyahu of seeking to block a ceasefire in the Gaza war with "heinous massacres" carried out by Israeli forces, a statement by the Palestinian group said.
The head of the political bureau of the group called on international mediators to act following two attacks in Gaza that Palestinian officials said killed more than 100 people.
An Israeli strike on the Al-Mawasi camp for displaced persons, which Israel said had targeted the Hamas military chief, left at least 90 dead and 300 wounded, according to the health ministry in the territory.
The civil defence agency said at least 20 people were killed in a strike on a makeshift mosque at Al-Shati refugee camp in Gaza City.
The Hamas statement said Haniyeh contacted officials in Qatar and Egypt, which are seeking to mediate in the war, as well as Oman and Turkey to discuss the "brutal massacres".
He said Hamas had shown "a positive and responsible response" to new proposals for a ceasefire and prisoner exchange, but "the Israeli position taken by Netanyahu was to place obstacles that prevent reaching an agreement", according to the Hamas statement.
Haniyeh also denounced comments made by Netanyahu as well as "new conditions and points" in the ceasefire proposal that was first outlined by US President Joe Biden in May.
"This is also linked to the heinous massacres committed by the occupation army today," he was quoted as saying.
Haniyeh called on the mediators "to do what is necessary with the American administration and others to stop these massacres". Qatar and Egypt have both condemned the Israeli strikes.
The statement said Haniyeh would hold more contacts.
Netanyahu has insisted that Israel will destroy Hamas and bring back all hostages taken during the Palestinian group's October 7 attack.
Following talks this week, Netanyahu also introduced a new condition that Israel must retain control of territory on Gaza's border with Egypt to stop arms smuggling to Hamas.
Netanyahu told a press conference on Saturday that Israel's military pressure had forced Hamas to seek a ceasefire, and that Hamas had sought 29 changes to the ceasefire proposal.
"I am not moving a millimetre from the outline that President Biden's gave his blessing to, but I am also not allowing Hamas to move a millimetre," Netanyahu said.