Tel Aviv, May 20 (IANS): The Israeli Army on Thursday said it "neutralised" an extensive tunnel system dug by the Palestinian Hamas militants in the Gaza Strip, keeping up its military offensive in the enclave as diplomats continued to search for a ceasefire deal.

The Israeli Defence Forces (IDF) said that its aerial assault and artillery bombardment continued overnight, hitting targets including the house of a Hamas commander in Khan Younis, an arms factory and rocket launchers, dpa news agency reported.

The IDF said that the tunnels were built over five years and allowed Hamas, which rules the Gaza Strip, to move ammunition, fighters and food within the coastal strip.

There was pressure on both sides to declare a ceasefire, with diplomats trying to spur a breakthrough after 10 days of fighting that has left more than 220 Palestinians and 12 people in Israel dead.

Tens of thousands of Gaza residents have fled their homes.

US President Joe Biden told Israeli Prime Minister Benjamin Netanyahu on Wednesday that he "expected a significant de-escalation" to start.

But Netanyahu said he was determined to continue its fight against the Palestinian Hamas militants "until its objective is achieved: to restore quiet and security to you, citizens of Israel".

German Foreign Minister Heiko Maas began a visit to Israel and the Palestinian Territories on Thursday to promote the international community's ceasefire efforts.

Maas is to hold talks with Netanyahu, Israeli Foreign Minister Gabi Ashkenazi, Defence Minister Benny Gantz and President Reuven Rivlin.

He will also meet Palestinian President Mahmoud Abbas.

Senior Hamas official Moussa Abu Marzouk told Lebanon's al-Mayadeen television that he expected "a ceasefire to be reached within a day or two".

"I think that the ongoing efforts regarding the ceasefire will succeed," he said, adding that he assumed any deal would only apply to hostilities in Gaza and not encompass issues related to unrest in the West Bank and Jerusalem.

"The talk is now on stopping fire only, and not on stopping any other form of resistance."

More rockets were fired by Palestinians at Israeli towns after midnight on Thursday.

According to the IDF, some 4,070 rockets were fired from the Gaza Strip in Israel's direction over the past week and a half.