A helicopter was to take off at dawn this morning from Chamonix to rescue the guide Olivier Sourzac, 47, and his client Charlotte Demetz, 44, who have been blocked since Thursday under the italian side of the "Pointe Walker", the top of the Grandes Jorasses (4208 meters) in the Mont-Blanc massif. Unfortunately, weather conditions didn't allow the flight. The two climbers were overtken by bad weather last Thursday after reaching the "Linceul" ("Shroud"), an extremely steep & technical ice wall. Since then, Chamonix guides have made two rescue attempts on foot, including Olivier Sourzac's brother, Bruno. Unfortunately, they were also abandoned, due to extremely poor weather. A emergency press conference will be held this afternoon in the Courmayeur Marie. Yesterday, very wet snow fell on the Grandes Jorasses, and it was impossible to mount a new rescue attempt on foot. It is thought that a helicopter rescue is now the last chance to recover Olivier & Charlotte alive. Everyone is now hoping for an improvement in the weather, to allow the helicopter to take-off.