The Palestinian militant groups Hamas (search) and Islamic Jihad (search) said Saturday they will not attack Israeli targets, but they refrained from officially joining a Palestinian cease-fire with Israel agreed upon during last week's summit in Egypt.

Leaders of both groups met Saturday with Palestinian leader Mahmoud Abbas (search), who is trying to keep the fragile cease-fire intact.

A Hamas leader, Mahmoud Zahar, told The Associated Press the group will wait to see whether Israel stops its military activities and targeted killings of Palestinian militants before deciding whether to join the truce agreed upon by Abbas and Israeli Prime Minister Ariel Sharon.

Zahar said after meeting with Abbas that Hamas was "committed to what is called 'quietness'" until it determines whether Israel meets its truce obligations, including disclosing the criteria for releasing Palestinian prisoners.

"Up to this moment, we are committed to the previous agreement with Mr. Abbas, and we are going to see how the Israelis" will act, Zahar told the AP.

Hamas, which opposes Israel's existence, pledged to Abbas it would stop attacks against the Jewish state as part of a general halt to violence by all militant groups. Hamas has killed hundreds of Israelis during the past four years of fighting.