Cairo: Israel has suffered "a psychological defeat" in Gaza and has failed to destroy the military infrastructure of the Islamic Palestinian movement Hamas, the group's deputy leader, Moussa Abu Marzuq, said in an interview with EFE in Cairo.

In a meeting at his residence on the outskirts of Cairo, Abu Marzuq explained that Hamas has remained in a state of "self-defence" during these weeks of conflict, and accused Israel of launching its aggression on Gaza "without a cause".

"The Israeli army has suffered a psychological defeat in the conflict in Gaza," Abu Marzuq said.

The senior Hamas leader said the militants' main achievement in the current conflict has been to prevent Israel from reaching its goals, including the destruction of the underground tunnel network in Gaza.

"Their plan will fail," he insisted.

His remarks came after Israeli Prime Minister Benjamin Netanyahu said the army would not end its operation in Gaza until it achieved its objectives and completed the destruction of the tunnels.

The withdrawal of Israeli troops has already begun in the Gaza Strip, according to Abu Marzuq, due to the death of dozens of Israeli soldiers.

He denounced the "scorched earth" policy of Israel in Gaza, which has destroyed thousands of homes with entire families inside, in addition to 50 mosques and 10 hospitals.

More than 1,830 Palestinians have been killed and 9,500 wounded since the start of Israel's Operation Protective Edge in Gaza July 8. None of the mediation efforts and truce announcements has so far succeeded to end the conflict.

"We defend our people and we have no purpose in this war. It was Israel who imposed war on the Palestinians," said the Hamas leader, who advocates negotiations.

In a further attempt to promote a ceasefire, a delegation comprising representatives of various Palestinian factions, including Abu Marzuq, have been meeting in Cairo with the mediation of Egypt since Sunday.

Israel is not part of the negotiations, and is awaiting a Palestinian proposal to decide its next steps.

Abu Marzuq expressed confidence that a solution would be reached, despite the current level of violence, noting that "there is no war that has no end".

"We hope negotiations can stop the Israeli aggression on Gaza, secure a truce and allow the people and the Palestinian resistance to attain their objectives," he said.

Although Hamas rejected an Egyptian ceasefire initiative in mid-July, Abu Marzuq insisted on thanking Egypt for its "indispensable role".

He also valued the stance of the Palestinian National Authority led by Mahmoud Abbas, despite differences with his group. 

"They support our rights and come with us on a unified delegation to defend Palestinians in Gaza," he said.

Hamas has demanded an end to the blockade on Gaza, the opening of border crossings, freedom of movement for people and goods, and the release of "unfairly" detained Palestinians in the West Bank.

Abu Marzuq said he saw only two alternatives in case talks fail: the first is a unilateral end to the Israeli offensive and the second is a new military occupation of Gaza.

The Hamas official considers the second option better for the Palestinians, because it would mean the reopening of border crossings and an improvement of the living standards in Gaza.

At the same time, military occupation would be very dangerous for Israel, as its soldiers would be an "easy target for resistance fighters".

Abu Marzuq recognised the "unequal balance of forces" if the conflict continued, but noted that Hamas's war of attrition would finally defeat Israel.

"Israel has all the military force but will lose the offensive on the ground and in terms of human rights, because it will be legally prosecuted for all its crimes in the international courts", he underlined.