Members of the National Resistance Brigades, the military wing of the Democratic Front for the Liberation of Palestine (DFLP), attend a news conference in Gaza City April 10, 2011. Palestinian militant groups in the Gaza Strip have agreed to Arab and United Nations proposals for a truce in the latest cross-border fighting with Israel, a Palestinian official close to the talks said on Sunday. [Photo/Agencies]

JERUSALEM - Israel's foreign minister says that working toward a cease fire with Hamas is a "grave mistake" and that his country should try to topple the militant Gaza rulers instead.

Related readings:  Gaza strip ceasefire 'possible'  Hamas makes rare appeal to Israel to halt fighting  Hamas warns against escalation of violence in Gaza  UN holds meeting on Mideast peace process

Avigdor Lieberman's remarks come as international mediators try to halt new fighting between Israel and Hamas that escalated dramatically last week to the most intense confrontation between the two since Israel's war in the Palestinian territory in late December 2008.

After a lull overnight, Lieberman told Israel Radio on Monday that Hamas exploits calm to build its fighting force and smuggle in weapons to use against Israel.

The military says Palestinians have fired more than 130 rockets and mortar shells into southern Israel since Thursday. Israeli reprisals have killed 19 Palestinians.