The Quartet of the United States, Russia, the European Union and the United Nations called on Israel in a statement "to take immediate steps, without endangering Israeli security, ... to facilitate rehabilitation and reconstruction by easing the flow of goods and people in and out of Gaza and the West Bank and between them".
The four big diplomatic players also urged Israelis and Palestinians to meet more frequently to hammer out plans for the mid-August Israeli pullout of Jewish settlers from Gaza.
"Contacts between the parties should now be intensified at all levels," said the statement issued after the powers met at ministerial level in London.
Major powers have generally praised the sides for working more closely together in recent weeks.
But Israeli and Palestinian leaders have repeatedly disagreed over how to balance what Israel says is the Jewish state's efforts at stopping fighters entering Israel with Palestinians' needs to move freely and more quickly through long lines at Israeli military checkpoints.