Defense Minster Ehud Barak on Thursday ordered the complete closure of the crossings from Israel into the Gaza Strip in the wake of the incessant Kassam rocket attacks. In a situation assessment Barak conducted with IDF officials, the defense minister ordered them to stop the transfer of trucks and goods into the Strip in order to exert pressure on Hamas. The defense establishment emphasized that the transfer of medicines and humanitarian aid would be allowed only in exceptional circumstances and only after a thorough examination. Earlier, Barak had ordered a continuation of the restrictions on Gaza fuel supply and instructed the defense establishment to allocate 260 million shekels for fortifications in Sderot and Gaza belt neighborhoods. Also Thursday, Barak said that Israel would deepen its operations in the Gaza Strip and stop the firing of rockets at the western Negev. Speaking during a visit to the area accompanied by IDF commanders, Barak said: "Even as we stand here, [Kassam] fire continues. The IDF will continue in its ongoing operation and deepen it in order to strike at the perpetrators, until the firing stops." "It won't be easy, it won't happen this weekend, but we will bring an end to Kassam attacks on Sderot," he added. Meanwhile, the Gaza operations got the seal of approval from the US, with US Assistant Secretary of State Sean McCormack saying that Israel has the right to defend itself from Kassam rocket attacks. However, McCormack urged the IDF to avoid harming innocent civilians, Israel Radio reported. Prime Minister Ehud Olmert said earlier that Israel would not tolerate the incessant Kassam rocket fire from the Gaza Strip and would act repeatedly against the Islamic Jihad, Hamas and all other Palestinian groups which continue to wage war on Israeli citizens. "We are not looking to fight in the Gaza Strip, we do not want to harm its residents and we have no special desire to kill any citizen," Olmert told the Israel Manufacturers' Association in Tel Aviv. "But we will not, and we cannot continue to suffer this relentless Kassam rocket fire on citizens of the state of Israel that emanates from there." The prime minister went on to commend the latest string of IDF operations in the Gaza Strip, which has so far killed at least 20 Palestinian operatives, and said that such military activity will continue until rocket attacks stop. "They absorbed a punch, and this punch is not the last one that they will absorb during this insufferable Kassam rocket fire on the southern Israel," Olmert said, promising that the Jewish state "will continue to act, with wisdom and with ferociousness, with maximal precision in order to hit all those who want to harm us, and without hitting innocent citizens, that are becoming victims of extremism, brutality, hate and incitement." Nevertheless, Olmert emphasized that there are no easy solutions to rocket attacks. "Unfortunately we can't just press a button to stop it." Earlier Thursday, Foreign Minister Tzipi Livni made similar comments during her visit to Moscow, saying that Israel would defend its citizens not only through negotiations, but also through "uncompromising war" against Palestinian terror from Gaza. "Israeli is obligated to its citizens, and needs to give a response to the daily attacks coming from Gaza," the foreign minister said, adding that "the answer to the Kassam rocket attacks is an uncompromising war on terror which originates from Gaza, and not only through dialogue and negotiations." "[Israel] must be clear: when speaking of a Palestinian state, we are talking about two parts - Gaza and the West Bank," the foreign minister continued. "The situation in Gaza must change," she concluded. Also Thursday, Vice Premier Haim Ramon said that Israeli military pressure on Hamas and other Palestinian organizations in the Gaza Strip would eventually bring an end the rocket attacks on the western Negev. "We already see a pretty major weakening within Hamas; a wish on their part to arrive at a cease fire," Ramon told Army Radio. "The easiest way to bring quiet to the Negev and Sderot will be if Hamas hold their fire." A senior Hamas official was quoted by Israel Radio as saying overnight Wednesday that Ismail Haniyeh's Hamas government would attempt to put a stop to Kassam rocket fire and other terror attacks emanating from the Gaza Strip. The source added, however, that it would be difficult to quell the flames so long as Israel continued aggressive operations in the Gaza Strip. On Wednesday, Defense Minister Ehud Barak said "We will increase the pressure on the Gaza Strip in order to bring an end to the Kassam rocket fire." Speaking during an opening speech at a Naval graduation ceremony in Haifa, Barak said Israel had no intention of softening its stance against terrorists and that military strikes in Gaza would continue as long as necessary.