"The Middle East is going through a very crucial moment, in several directions," said the European Union's top diplomat as he left Cairo at the end of a six-day tour to assess developments in the region first hand.

"We think that the centre of gravity, in order to solve the problems of the Middle East, has to be given a push on the Palestinian-Israeli track," he told reporters travelling with him.

"Without solving that we will have very little chance," he added.

During his trip, Solana spoke with leaders in Israel, the Palestinian territories, Lebanon, Jordan and Egypt, with most discussions focusing on how to get the Jewish state and the embattled Palestinians talking again.

Achieving that, EU officials say, could be a key that unlocks other parts of a vastly complicated Middle East puzzle stretching from Egypt up to Lebanon, over to Syria and then across to Iran.

Domestic concerns for Israel and the Palestinians are severely hampering progress, however.

Israeli Prime Minister Ehud Olmert's government has been badly weakened by its 34-day summer war against Shia Hezbollah militants in Lebanon, which coincided with a second front in the poverty-hit Gaza Strip.

In fresh violence on Tuesday, Israeli troops killed two Hamas militants in the Gaza Strip during clashes between Palestinian gunmen and soldiers, Palestinian doctors said.

An Israeli army spokeswoman said an operation was taking place against militants in the area, near the town of Khan Younis, and that troops shot at a group of gunmen who tried to plant a bomb near soldiers.