Israel's security Cabinet on Tuesday approved an army plan to intensify targeted killings of Palestinian militants and send more troops into the Gaza Strip for ground operations, a security official said.

The military campaign will last several weeks, the official said on condition of anonymity.

The planned attacks were intended as retaliation for a double suicide bombing at an Israeli seaport earlier this week, the first deadly attack on a strategic target.

The strikes are also meant to increase pressure on militants, particularly the Islamic militant group Hamas (search), ahead of a possible Israeli withdrawal from Gaza.

Security officials said the military was expected to intensify targeted killings of Palestinian militants and launch large-scale raids in the Gaza Strip (search), from where the bombers were sent. Sunday's attack on the Ashdod (search) seaport, about 25 miles north of Gaza, killed 10 Israelis.

The Cabinet meeting lasted for more than three hours. Participants declined to comment on the discussions, but Israeli media said ministers approved more targeted killings, including of militant leaders, and a limited ground operation in Gaza.

The Cabinet reportedly also decided to expand a closure, already in effect in Gaza, to the West Bank, meaning Palestinians will be barred from Israel until further notice.

Asked whether an Israeli crackdown would be effective, Justice Minister Tommy Lapid said: "You never finish with terror. You can only fight terror."

Said Siyam, a spokesman for the Islamic militant group Hamas in Gaza, warned that Israel would pay a heavy price for any military strike in the strip.

The Ashdod bombing shook Israel's security establishment because of the relative ease with which the attackers got into the heavily guarded port from fenced-in Gaza. The port, which has large storage tanks of fuel and hazardous chemicals, is considered a "strategic" target, meaning an attack there could lead to hundreds, if not thousands, of casualties.

The bombing was seen as part of an escalation triggered by Prime Minister Ariel Sharon's talk about a possible withdrawal from much or all of Gaza and some of the West Bank. Both the militants and the Israeli military are trying to claim a pullback as a victory, with armed groups already bragging that they are forcing Israel out. Israel wants to avoid the impression of being seen as fleeing the strip.

The withdrawal, which would include dismantling some settlements and imposing a boundary on the Palestinians, is part of Sharon's unilateral "disengagement" plan. He has said he would go ahead if peace efforts remain frozen in coming months.

Sharon never declared formally that he is abandoning attempts to negotiate a peace deal. However, on Monday, he told Israel's parliament that "there is no Palestinian leader with the courage, the ability, to struggle against terrorism" and that "clearly, in this situation, there will be no peace talks."

After the Ashdod bombing, Sharon also canceled a summit with Palestinian Prime Minister Ahmed Qureia, which had been tentatively set for this week.

Qureia said Tuesday he is still willing to negotiate with Israel, and accused Sharon of trying to avoid peace talks. The Palestinians suspect Sharon is shying away from negotiations because he believes he can hang on to more West Bank land with his unilateral plan.

"A Palestinian partner exists and is committed to the peace process, but the Israelis are running away from their responsibilities," Qureia told an economic conference in the West Bank town of Ramallah.

On Tuesday, Sharon convened his security Cabinet and several key ministers to decide on a response to the Ashdod bombing.

A security official, who spoke on condition of anonymity, said the military is expected to intensify targeted killings of Palestinian militants and launch more raids in Gaza to try to draw gunmen into firefights.

Defense Minister Shaul Mofaz consulted with top security officials Monday. Israel Army Radio said Mofaz' recommendations to the Cabinet include "actions on a scale, dimension and time frame that have not been seen for a long time."

A retired army general, Yaakov Amidror, told Army Radio that the military should strike Gaza with all its might ahead of a withdrawal.

"This will require staying in the area at least for weeks, so we can really deal with the terror infrastructure," he said.

In response to the Ashdod bombing, the military indefinitely closed the Erez crossing between Gaza and Israel, keeping some 19,000 laborers from jobs in Israel. Military officials said there is concern that the bombers, a pair of 17-year-old high school students, used forged IDs and permits to get through Erez.

A militant leader in Gaza, who identified himself only as Abu Qusay, has said he believed the bombers crawled through tunnels. Abu Qusay said bombers had planned to blow up large fuel tanks at Ashdod port. However, the explosions went off hundreds of yards from the tanks.

The bombing was carried out by the Islamic militant Hamas movement and the Al Aqsa Martyrs' Brigades, a group with ties to the Fatah movement led by Yasser Arafat and Qureia.