At the same time Hamas's exiled political chief, Khaled Meshaal, insisted that Gilad Shalit, the captured soldier at the heart of the crisis would not be freed without a swap for Palestinian prisoners.
Israel has refused to negotiate with Hamas or free prisoners in exchange for the missing teenage corporal.
"We haven't set a particular timetable for this operation. We will continue in places, in time, in measures that will suit our purposes," said Mr Olmert, who is facing the biggest test of his premiership in the crisis.
"I think that once the Qassam (rocket) shooting will be stopped and the terrorist actions against innocent civilians will be halted altogether, there will be no need for any Israeli action in Gaza," he said.
Hamas political leader fronts media
In a rare news conference in Damascus exiled Hamas political leader Khaled Meshaal declared that the captured soldier was being treated as a prisoner of war.
"There will be no freedom for the Israeli prisoner without an exchange involving Palestinian detainees," he stressed, while vowing that Corporal Shalit's life would be protected.
At least 50 Palestinians and one Israeli soldier have been killed since
Israel tanks and troops poured into the Gaza Strip on July 5 in a bid to stop Palestinian rocket attacks and secure Corporal Shalit's release.
Among the latest deaths were four Palestinian teenagers and another four people were wounded in Israeli air strikes over the Gaza Strip.
Witnesses said the victims were playing football close to an area where militants had fired makeshift rockets towards Israel a short time earlier.
One rocket was reported to have landed on Israeli territory without causing damage or casualties.
An Israeli army spokeswoman said the air raid had targeted a rocket-launching cell in northern Gaza in the Beit Hanun area.
Two militants from Hamas's armed wing and two from rival Islamic Jihad were killed in earlier strikes, and at least another 12 bystanders were hurt. An eighth Palestinian died of his injuries elsewhere in Gaza.
Long haul
Israel has warned that troops are likely to be in for the long haul, rejecting a call by Palestinian Prime Minister Ismail Haniya for a mutual ceasefire but denying that the offensive aims to topple his Hamas government.
Meanwhile, Palestinian president Mahmud Abbas left on a surprise visit to Jordan for talks with Prime Minister Maaruf Bakhit at the request of King Abdullah II to discuss regional developments.
Aid groups have also expressed concern about the difficulties of assisting 1.4 million people living in Gaza following months of financial crisis and the suspension of direct Western aid to the Hamas-led government.