Acting Foreign Minister Tzipi Livni appealed to the international community on Friday not to legitimize a Palestinian government led by Hamas, saying that elections are not a "laundry" for terror groups. Speaking to reporters Friday, Livni said that Israel's withdrawal from the Gaza Strip last summer opened a window of opportunity in peace efforts between Israel and the Palestinians. With the election of Hamas "the Palestinians slammed it shut," she said. Also on Friday, Defense Minister Shaul Mofaz instructed the army to continue arresting Hamas terrorists and to step up pressure on Islamic Jihad, which carried out last Thursday's bombing in Tel Aviv. His instructions followed a security assessment that indicated that the terror group might try to take advantage of the situation following the Palestinian elections and escalate terror against Israel, in order to try to establish itself as the vanguard of the armed struggle against Israel. Acting Prime Minister Ehud Olmert declared during a security cabinet meeting Thursday night that any Palestinian Authority government that included Hamas would not be a partner for Israel. "If a [Palestinian] government should arise of which Hamas is a participant, the world and Israel will ignore it and render it irrelevant," Olmert said. The Prime Minister's Office issued a statement after the Thursday night cabinet meeting that read, "Israel will not negotiate with a Palestinian government, even if only part of it is an armed terrorist organization calling for Israel's destruction, and in any case will continue to strenuously fight terrorism everywhere." Although little information leaked out of the evening's security cabinet meeting, diplomatic officials said that Prime Minister Ariel Sharon's top adviser Dov Weisglass and Giora Eiland, the head of the National Security Council, were at loggerheads over Israel's policy toward the elections. According to these officials, Eiland said that Israel should never have allowed Hamas to take part in the elections and blamed Weisglass for championing a policy that let it participate because he did not want a confrontation with the US, which was in favor of Hamas participation. The officials said that Weisglass' argument was that Israel should not go to battle with the US over this issue before the vote, because whatever the results, it would need US support afterward. Channel 2 reported that this disagreement was part of a larger dispute between the two, with Eiland interested in becoming the head of Olmert's foreign policy team, something that would effectively shunt Weisglass aside. Olmert effectively muzzled his ministers and government spokesmen Thursday as the government grappled with how best to deal with a brand new reality: "Hamastan," following the Hamas victory in the Palestinian elections. Consultations were held throughout the day in both the Foreign and Defense ministries, and Olmert convened a meeting of the security cabinet in the evening. In addition, senior diplomatic officials were in close contact with the White House and State Department to coordinate moves over the next few days. While Israel's long-term policy toward the new reality was still being formulated, one senior diplomatic source said that in the short term, Israel's policy would be to speed up the construction of the security fence, continue strikes against terrorist targets and mobilize international pressure on Hamas to change its ways or suffer the economic consequences. One official said that Israel was in no rush to "shoot from the hip," and wanted to carefully explore the various options. He said Israel also wanted to wait to respond until it saw how the international community weighed in. The country's response, diplomatic officials said, would also be dependent on the final make-up of the Palestinian Authority government. Livni met Thursday afternoon with EU special envoy Marc Otte, and Olmert met in the early evening with Quartet representative James Wolfensohn in advance of a key meting of the Quartet in London on Monday. Livni told Otte that after the Hamas victory, the EU must make it clear that Europe would not look understandingly upon a process that would lead to the establishment of a "terrorist government." The EU's foreign ministers are also scheduled to meet on Monday. Livni also talked during the day with US Secretary of State Condoleezza Rice, and US Ambassador Richard Jones was in Jerusalem holding talks throughout the day. TheAssociated Press contributed to this report.