As US envoy David Welch wrapped up his visit to the region Saturday, Israel maintained its stance that Palestinian convoys between the Gaza Strip and the West Bank are unacceptable due to security concerns. Under an agreement brokered by the US, IDF-escorted buses were supposed to start running between Gaza and the West Bank on Thursday. Last week, Israel suspended discussions on beginning the convoys after the Palestinian Authority allowed terrorists to enter the Gaza Strip via the Rafah crossing along the Egyptian border. The opening of Rafah was the central component of the US-backed deal. "This prime minister is not going to repeat the mistakes of the past," when Israeli leaders turned "a blind eye" to PA transgressions, said Prime Minister Ariel Sharon's spokesman Ra'anan Gissin. He said there was no change in Israel's policy on the convoys. Defense Minister Shaul Mofaz also warned that the IDF could step up security checks of Palestinians at the Karni and Erez crossings into Israel if security concerns are not better met. He is due to receive a report from Kerem Shalom - from which Israel observes who is crossing into Gaza - to see whether security conditions have improved, after which a decision will be made about Karni and Erez. Welch, assistant secretary of state for the Near East, addressed the issue during his three days of meetings with Israelis and Palestinians. The PA pushed Welch on the convoy issue, and stressed the importance of implementing the agreements. Members of the international community have also indicated their concerns over how the convoy freeze could affect economic development. One Western diplomatic source on Saturday called Israel's "unilateral freezing" of the agreement's implementation "unwarranted" and warned it "may torpedo" next week's conference in London of donors interested in developing the PA economy. "This could endanger Israel's diplomatic achievements following disengagement," he said. The Americans have acknowledged the importance of the convoys, and their interest in developing the PA economy. However, they tend to use "target date" when referring to December 15 and have emphasized that Welch's visit here focused on the need for the PA to fight terror. "We understand the Israelis' need to protect themselves against acts of terror," said US Embassy spokesman Stewart Tuttle, adding, "We urge both sides to weigh decisions they take very carefully, and think about the implications of the actions they take, and not to exacerbate the situation." In his meeting with Welch, PA Chairman Mahmoud Abbas claimed that the PA was fulfilling its security commitments and has even managed to thwart attempts to smuggle weapons and drugs from Egypt. PA Civil Affairs Minister Muhammad Dahlan, who is in charge of the border crossings, said after the meeting that the PA was in full control of the terminals in line with the agreements reached with Israel with the help of the US and the European Union. He said Abbas raised the issue of the "safe passage" between the West Bank and Gaza Strip, expressing hope that the Palestinians would soon be able to operate bus convoys on this route. According to Dahlan, the two sides also discussed preparations for next month's parliamentary elections in the West Bank and Gaza. He said there was a need to coordinate a number of issues and arrangements with Israel ahead of the vote.