JERUSALEM, June 19 (Xinhua) -- UN envoy to the Middle East Robert H. Serry praised Thursday the ceasefire in the Gaza Strip starting from Thursday morning, saying the agreement is an "encouraging sign" to achieve security.

　　"I believe that a ceasefire agreement between Israel and Hamas is an encouraging sign that will lead to quiet and security from both sides," Serry was quoted by local daily Yedioth Ahronothas assaying.

　　However, Serry said caution must be maintained toward the peace deal.

　　"We are aware of the fact that both sides claim the ceasefire is frail. We need to be realistic with little expect that achievements will be immediate," he said.

　　According to Serry, the three issues that must be emphasized in the near future are a complete ceasefire, opening the Gaza border crossings, and prisoner exchanges including Gilad Shalit, an Israeli soldier who was kidnapped by Gaza militants in a 2006 cross-border raid.

　　Next week, Middle East Quartet representatives will meet in order to discuss additional steps to achieve a calm in the region, Serry added.

　　UN Secretary-General Ban Ki-moon on Wednesday welcomed the announced cessation of violence relating to Israel and Gaza.

　　"The secretary-general hopes that these efforts will both provide security and an easing of the humanitarian situation in Gaza, and end rocket and mortar attacks against Israeli targets," his spokesperson said in a statement.

　　Ban also said he hopes that the Gaza border crossings will be open for humanitarian and commercial purposes and praised the Egyptians for their efforts to achieving a calm.

　　Israeli government spokesman Mark Regev said Wednesday that if the fighting indeed ceases as planned, Israel will ease its blockade of Gaza next week.