Hamas condemned Israel for violating the terms of the cease-fire, maintaining its troops along Gaza's southern border with Egypt, stating they should have withdrawn under the terms of the deal.
The Philadelphi Corridor, a strip of land on the Palestinian side of the Egypt-Gaza border also known as Salaheddin axis, has been a key sticking point in cease-fire negotiations between Israel and the Palestinian resistance group Hamas.
"The Israeli occupation did not abide by the gradual reduction of its forces in the Salaheddin axis during the first phase" of the truce which began on Jan. 19, Hamas said in a statement.
It added that Israel "did not begin its withdrawal on the 42nd day as stipulated in the agreement," and had not completed it "by the 50th day of the agreement, which was yesterday (Sunday)."
In its statement, the Palestinian group said that Israel's "failure to withdraw from the Philadelphi Corridor" was a "blatant violation" of the cease-fire agreement "and a deliberate attempt to undermine and nullify it."
Israeli forces seized control of the Philadelphi Corridor in southern Gaza last year.
"Maintaining absolute control over the Philadelphi Corridor is non-negotiable from a security standpoint," Defense Minister Israel Katz has said.
Hamas called on mediators Qatar, Egypt and the United States to intervene and ensure that Israel withdraws its forces.
"We demand that the mediators and the international community intervene immediately to ensure the occupation's withdrawal and the resumption of the second-phase negotiations without delay," the group said.
Earlier on Monday, Israel sent a team of negotiators to Doha for talks aimed at extending the cease-fire.
Its first phase expired on March 1, with no agreement yet on subsequent stages that could secure a lasting end to the war.
Hamas wants immediate negotiations on the next phase, but Israel prefers extending phase one.
The United Nations said Monday that Israel's decision to cut off electricity to Gaza was "very concerning," warning that civilians in the war-ravaged Palestinian territory would face dire consequences.
Israel has halted aid deliveries to the Gaza Strip and has now cut its electricity supply, disconnecting the only power line to a water desalination plant in order to ramp up pressure on Hamas.
"Israel's decision to cut off electricity to Gaza following its ban last week on the entry of all humanitarian assistance and other necessities of life, including fuel needed to operate generators, is very concerning," Seif Magango, spokesman for the U.N. human rights office, told AFP in an email.
"With no electricity and with fuel being blocked, Gaza's remaining water desalination plants, healthcare facilities, and bakeries are at risk of eventually shutting down, with dire consequences for civilians."
Magango said that as the occupying power, Israel had a legal obligation to ensure the provision of the necessities of life for Palestinians living under its control.
"In addition, blocking access to the necessities of life for civilians intended to pressure a party to an armed conflict through hardship imposed on the civilian population as a whole raises serious concerns of collective punishment," he added.
Israel's negotiating team left for Qatar on Monday to attend talks aimed at extending the fragile Gaza cease-fire.
