Israel is delaying talks on re-opening Gaza's border crossings, an international envoy who is helping with reconstruction in the strip has said.
Mr Wolfensohn's comments came in a letter to the UN secretary general
In a letter to the UN, James Wolfensohn said Israel was reluctant to loosen its control over Gaza.
Israel denied it was foot-dragging, saying it had legitimate security concerns that needed to be addressed.
Mr Wolfensohn said Israel was "almost acting as though there had been no withdrawal" from the Gaza Strip.
He said there needed to be quick progress on improving Palestinian movement and access to the outside world if the economic revival essential to peace was to happen.
"The government of Israel, with its important security concerns, is loath to relinquish control, almost acting as though there has been no withdrawal, delaying making difficult decisions and preferring to take difficult matters back into slow-moving subcommittees," Mr Wolfensohn wrote in a letter to Kofi Annan, obtained by Associated Press.
Mr Wolfensohn, a former head of the World Bank, was named as a special representative of the Middle East "quartet" (the UN, Russia, EU and US) earlier this year.
His task is to help co-ordinate reconstruction efforts after the withdrawal of Israeli settlers and soldiers from Gaza. Israel continues to control the external borders, coastline and airspace of the territory.