JERUSALEM - Israel's outgoing prime minister called on hard-line Likud leader Benjamin Netanyahu to form a new government quickly as coalition bargaining shifted into high gear Sunday.

Opening the weekly meeting of his soon-to-be-dissolved Cabinet, Prime Minister Ehud Olmert said Israel needed a new government soon.

Negotiators should "conduct things in an effective and fast way in order to establish, as quickly as possible, a government that will enjoy full authority and will be able to rule effectively," Olmert said.

Olmert is a caretaker prime minister until Netanyahu can form a new ruling coalition. After having been entrusted with the task of forming a new government by President Shimon Peres on Friday, Netanyahu now has six weeks to do so.

The question is whether he will form a narrow coalition with his hard-line allies or a broad centrist coalition with his rival, Kadima Party leader Tzipi Livni. The two were slated to meet later Sunday.

Netanyahu could form a narrow coalition with relative ease, giving him 65 seats in the 120-seat parliament. But that narrow margin would give his smaller coalition partners effective veto power over any decision, as they could bring down the government in a dispute. Such an alliance would also likely freeze peace talks and could clash with the U.S. administration.

Bringing in Livni would reduce international pressure on Israel and provide more stability but she has said she will enter the government only if Netanyahu agrees to a "rotation" arrangement whereby each would serve as prime minister for half of the government's four-year term. Netanyahu rejects that condition. And Livni supports the formation of a Palestinian state alongside Israel, while Netanyahu does not.

One of Livni's party colleagues, Cabinet minister Meir Sheetrit, said Kadima would not join a government that would call off peace talks with the Palestinians.

"We cannot be in a government that will not go for peace, because if we do so, Kadima could be deleted from the political map," Sheetrit said.

Responding to the demands, Netanyahu called on Livni to enter talks without preconditions and said he planned to ask both Kadima and the centrist Labor Party to join him in the government.

"Unity can be achieved by dialogue, not by dictates, not by arm-wrestling. That's what we will do today -- we'll begin the effort to join hands, first with Kadima, and tomorrow with the Labor Party," Netanyahu said.

Netanyahu spoke ahead of a meeting with visiting Sen. Joe Lieberman, who said he believed that a Netanyahu-led government would enjoy good relations with Washington.

"Our enemies, unfortunately, are as common as the values and the interests that have united us for all these years," Lieberman told reporters. "I have no doubt that with Netanyahu's government here we will have good and positive relations."

Lieberman also met with Avigdor Lieberman, whose Yisrael Beiteinu party saw its support surge in the recent elections and is now the third-largest grouping in parliament. Lieberman's party ran on an anti-Arab platform and has drawn charges of racism, but is all but assured of an important role in the new Israeli government because of its newfound clout.

With Israel between governments, sporadic violence is continuing along the Gaza border in the absence of a long-term truce with the radical Islamic Hamas, which rules there. Israel halted a military offensive in the territory on Jan. 18.

Gaza militants fired a rocket into Israel early Sunday, police spokesman Micky Rosenfeld said. There were no injuries.