Israel has introduced what it said was a new U.S. ceasefire plan and is trying to force Hamas to accept it by imposing a siege on the Gaza Strip.

Israel's Prime Minister Benjamin Netanyahu threatened Hamas on Monday with unimaginable consequences if it did not return hostages held in Gaza, while the Palestinian group accused his government of sabotaging the truce.

A delicate truce between Israel and Hamas hangs by a thread after Israel blocked humanitarian aid into Gaza, in response to Hamas rejecting a new Israeli proposal to extend the ceasefire without any commitment to end the war or fully withdraw troops.

Channel 12, on March 1, reported that Israeli troops have been drilling for a renewal of the war, a return to the Netzarim Corridor in central Gaza, from which Israel withdraw recently, and the removal of Palestinian civilians from northern Gaza to humanitarian zones in the south.

The move was apparently part of a bid to force Hamas into accepting a temporary extension of a cease-fire and releasing more hostages.