"Should the lull not be maintained, we will respond with full force," he said.
"We agreed on a ceasefire that puts an end to the military buildup, Qassam fire, mortar shell fire, and any kind of terrorist activity directed at southern communities," he said.
'Syria talks to continue'
Turning his attention to indirect negotiations with Syria, the prime minister said that the indirect talks will continue until the process matures into negotiations that lead to a comprehensive peace deal."At the same time, we shall continue our talks with the Palestinians. I will be meeting with (Palestinian leader) Mahmoud Abbas and continue the indirect meetings with Syria," the prime minister said.
Before his speech, PM Olmert toured the nuclear reactor in Dimona and met with senior officials at the site.
'Sea of peace'
Meanwhile, Palestinian President Mahmoud Abbas expressed hope that a lasting peace deal with Israel could be reached before the end of the year, ahead of a meeting with Defense Minister Ehud Barak on Tuesday.
Abbas, who joined Barak and Iraqi President Jalal Talabani at a Socialist International conference in Greece, said his government would work to keep alive the truce between Israel and Hamas.
"Israel will live in an island and sea of peace if Israel withdraws from Arab and Palestinian territories," Abbas told the conference. "We witness some steps in this direction which may stop this violence and bloodshed... Now there has been an agreement and we hope it will be kept. We want to keep this truce going.
"We hope that before the end of this year, and this is a hope, we can reach a true agreement for the end of the occupation and violence ...between Israel and Palestine," Abbas said, qualifying his statements by adding that "the painful truth is that we still have a long way to go to achieve success."