Greeks are extremely anti-Israel and pro-Palestinian. They have had long love affair with Arafat and Palestinian militants. Greek public would not tolerate Papandreu's visit to Israel. Israel is desperately trying to build an anti-Turkish alliance in the region with Greeks, Greek Cypriots and Armenians but they are all pro-Palestinians. The only way which could convince them would be bribes for their corrupt politicians. Otherwise, their public is anti-Israel.
from the article: Greek PM to arrive in Israel next week for first such visit in 3 decades