"Our duty to the fallen and their families is to make every possible effort to traverse the long path which leads to preventing war and to peace," Olmert told those assembled.
At 8 pm, a one-minute siren, marking a moment of silence in honor of Israeli fallen soldiers and terror victims, will be heard across the country.
The siren will be directly followed by the official memorial service at the Western Wall plaza. National flags will be flown at half mast.
"Night is falling on the hills of Jerusalem, and the country is enshrouding itself in silence. It is the silence of pain. It is deep, wounded and tormented. At this time on the eve of Memorial Day, the State of Israel is gathering in mourning and is joining together in memory of its sons and daughters who fell in Israel's wars," Olmert opened his speech.
"We never wanted battles, we are a people who holds life holy. We do not rejoice in war, but time and again we are forced to protect ourselves, to fight for our freedom – we are ready to go to battle but we do not like war. Even when we achieve our goals, we are not carried away by the joy of victory because the price we pay is so heavy," Olmert said.
'May Lebanon war be last war'
The prime minister spoke of the victims of the Second Lebanon War. "In the year that passed since last Memorial Day, we went to war on the border with Lebanon, the Second Lebanon War. This war is another link in the grievous chain of Israel's wars against an enemy who still has not come to terms with our existence.
"This war, too, exacted a dear and heavy price from us. What we would give for this to be the last war, that the war casualties and disabled would know relief for their pain, that we see the hostages return home soon.
"We are an ancient people, we were born here and we have the strength to stay here forever. The chapters in the short lives of the victims are the unequivocal testimony to this, but we will never despair from attaining the peace we yearn for so much. We are attentive to what is happening across the border, and we also hear the strengthening of moderate voices," Olmert said.
The prime minister spoke of the personal pain of mourning.
"Every one of the victims is a world in its entirety, forever lost, a hollow which can never be filled. I know this pain is personal and intimate. Even when the entire nation mourns together, the pain will always be private. I know that words are no consolation, and there is no way of understanding what you, parents, widows, orphans, brothers and friends, feel every day of the year. Only rarely can words express the anguish of parting."
Peretz: We stand ready to shield nation
Defense Minister Amir Peretz sent a letter to bereaved families. "The reverberations are still subsiding of yet another war in the chain of wars which shield the nation of Israel. Once again we set out to protect our home from the aggressive sword, but once again at the price of the lives of the best of our sons.
"We are seekers of peace and do not rejoice in war. But we learned this: We must not be restrained in the face of belligerence, because that will only invite more aggression.
"The sacrifices, courage and devotion of the IDF's soldiers have thwarted enemy plots and paved the way for peace with our neighbors to the south and east. Our mission now is to draw from the spirit of the fallen and stand steady and strong, in full military readiness and fitness, to repel any threat to Israel's security. We must work simultaneously through every channel and be willing to make painful concessions to complete the circle of peace," Peretz wrote.
At 11 am Monday morning a two-minute siren will open the memorial services in 43 military cemeteries across Israel and at the Memorial for Fallen Bedouin Soldiers at Hamovil Junction.