With Operation Cast Lead entering what appears to be its closing act, Egypt will soon need to prove whether it can provide Israel the security guarantees it is seeking in the form of a complete halt of weapons smuggling along the Philadelphi Corridor. Since the beginning of Operation Cast Lead, Israeli officials said that ultimately it would be up to Egypt to mediate a new truce with Hamas. While France and Turkey took a swing at mediation, there was never a doubt in the Israeli defense establishment that Egyptian President Hosni Mubarak and Intelligence Minister Omar Suleiman had the most clout. Egypt is in a unique position because it enjoys diplomatic ties with both Israel and Hamas. Suleiman, believed to be the second-most-powerful person in Egypt and a potential successor to the 80-year-old Mubarak, has been entrusted with the "Israeli file." His main interlocutor on the Israeli side is Amos Gilad, head of the Defense Ministry's Diplomatic-Security Bureau. The basis for a cease-fire with Hamas are well known: Israel wants a cessation of rocket and terror attacks, while Hamas wants the reopening of the border crossings, including at Rafah, as well as an immediate withdrawal of Israeli troops from the Gaza Strip. Israel's second demand - to halt the weapons smuggling into Gaza - is the most complicated. Without this condition, top IDF officers said last week that Hamas would have been prepared to sign on a new cease-fire. Israel's insistence that the smuggling into Gaza be stopped is based on the lessons it learned from Security Council Resolution 1701, which ended the Second Lebanon War but did not put an end to the smuggling of weapons from Syria into Lebanon. Since then, Hizbullah is believed to have nearly tripled its missile stockpile from 15,000 to over 40,000, including missiles with longer ranges and larger warheads. The fear in Israel is that if the smuggling into Gaza isn't stopped, then Hamas will do the same. Since the beginning of Operation Cast Lead Israel has destroyed over 250 tunnels along the Gaza-Egyptian border. But at least 100 remain and Hamas, intelligence officials said this week, is still trying to smuggle advanced weaponry, including such items as long-range rockets and high-grade explosives, into the Strip to be used in the battle against the IDF. Israel and Egypt do not see completely eye-to-eye on how to stop the smuggling. Ideally, Israel would like to see the deployment of a multinational force on the Egyptian side of Rafah to assist the Egyptians in detecting and destroying the tunnels. Cairo immediately rejected the idea, saying it would never allow a foreign military presence on its sovereign territory. Israel then hoped to extract a memorandum of understanding from the Egyptians in which they would commit to stopping the tunnels. This too, was rejected by the Egyptians, leading Israel to realize that the most it will get is a verbal commitment, as well as help from the United States, which will supply technology and come up with innovative ideas on how to stop the smuggling. Israel has made several proposals, from building a moat along the border to erecting a barrier surrounding the Egyptian side of Rafah that will be manned by Egyptian soldiers who will not allow weapons smugglers into the village. The US and Germany have already donated tunnel-detection technology to the efforts. Despite all of this, Egypt has persistently asked Israel to allow it to increase the number of border policemen it has deployed along the Philadelphi Corridor. Following Israel's withdrawal from Gaza in 2005, Egypt was permitted - in line with the Camp David Treaty - to deploy 750 policemen along the border with Gaza to be used to locate and destroy Hamas weapons-smuggling tunnels. Egypt claims that it is impossible to effectively combat the smuggling with only 750 border guards, since only one-third are on duty at any given time, with the rest of the force either on leave or in training. Israel has over the years rejected the request for an increase, but this week senior defense officials said that if Egypt wants more soldiers then Israel should just let it have them. This way, the officials said, Egypt would not have any excuse not to cooperate, and Israel could see if Cairo was sincere or not.