Olmert, speaking to foreign media, also reaffirmed his commitment to his plan to redraw the Jewish settlement map in the occupied West Bank, but acknowledged "this will be difficult."

He said in forceful tones that he would not negotiate with the governing Hamas movement for the release of the young corporal, taken to Gaza in a cross-border raid on June 25.

Militant groups that kidnapped the 19-year-old tank gunner have demanded Israel free more than 1,000 Palestinian prisoners.

"I will not release prisoners for the trade of Corporal Gilad Shalit to Hamas," Olmert said.

In Gaza, senior Hamas legislator Mushir al-Masri said failure to meet the militants' demands would only put the soldier more at risk.

"The Zionist enemy should not dream that the Palestinian people will ever accept releasing the captured Israeli soldier for free," Masri said.

Lashing out at the European Union, which has been outspoken in its criticism of Israel's ground and air assaults, Olmert said the bloc should have focused instead on daily rocket fire by militants in Gaza against the Jewish state.

"When was the last time that the European Union condemned this shooting and suggested effective measures to stop it?" Olmert said. "At some point, Israel had no choice but to take some measures in order to stop this thing."

He said Israel had "no particular desire to topple" the Hamas-led Palestinian government despite the arrest by the Israeli military of dozens of Hamas officials and its Gaza raids.

The European Union has accused Israel of disproportionate use of force against Palestinians in Gaza and of making a humanitarian crisis there worse.

Some 50 Palestinians, including about 20 civilians, have been killed since the Israeli offensive began, Gaza residents said.

In the latest violence, Israeli air strikes in the Gaza Strip killed one militant and wounded five others.

"We haven't set a particular timetable for this operation (in Gaza). It will continue in places, in times, in different measures that will suit the purposes that were outlined," Olmert said, repeating what he told his cabinet on Sunday.

"I will stop when I will feel that I can provide security for the people of Israel. I will not stop until then," he said.

Israel Radio said militants in Gaza fired three rockets at southern Israel early on Monday, causing no casualties.

The Israeli offensive has continued despite expressions of concern from the EU and United Nations at the worst fighting between Israelis and Palestinians since 2004. Israel's main ally, the United States, has been less critical.

Early on Monday, the Israeli army said an aircraft destroyed a weapons depot belonging to the Islamic Jihad faction, which, like Hamas, is committed to destroying Israel.

Olmert said he had not changed his "basic commitment to the realignment plan" to remove isolated Jewish settlements in the occupied West Bank while strengthening large blocs.

The plan, which Palestinians have condemned as effective annexation of land they want for a state, has been largely sidelined by events in Gaza and met with scepticism by some world leaders, who have voiced opposition to unilateral moves.

"I am absolutely determined to carry on in order to ultimately separate from the Palestinians and to establish secure borders that will be recognised by the international community," he said.