The Israeli army announced "extensive ground operations" on Sunday as part of its newly expanded campaign in the Gaza Strip, where rescuers reported dozens killed in a wave of Israeli strikes.

The announcement came just hours after Prime Minister Benjamin Netanyahu signalled Israel was open to a deal with Hamas that involved "ending the fighting" in the besieged Palestinian territory.

The military said that over the past day, troops had "begun extensive ground operations throughout the northern and southern Gaza Strip".

It said they had "eliminated dozens of terrorists, dismantled terrorist infrastructure... and are currently being deployed in key positions".

Israel says its ramped-up campaign aims to free hostages and defeat Hamas, but as the early operation's stages got underway Saturday, Israel and the group were entering indirect talks in Qatar aimed at hammering out a deal.

In a statement Sunday, Netanyahu's office said "the negotiation team in Doha is working to exhaust every possibility for a deal -- whether according to the Witkoff framework or as part of ending the fighting", referring to US Middle East envoy Steve Witkoff, who has been involved in previous discussions.

Netanyahu's statement said such a deal "would include the release of all the hostages, the exile of Hamas terrorists, and the disarmament of the Gaza Strip".

Since a two-month ceasefire collapsed in March as Israel resumed its offensive, negotiations mediated by Qatar, Egypt and the United States have failed to reach a breakthrough.

Air raid sirens sounded in southern Israel on Sunday afternoon, as the army said two projectiles were launched from Gaza, with one intercepted.

The military later issued an evacuation order for several parts of Gaza ahead of an attack, warning it would "launch a powerful strike on any area used for launching rockets". (AFP)