Unless negotiations to end the Gaza war succeed in lifting a blockade of the territory, Gazans will not see any improvement in their lives for at least another 15 years.

Unless negotiations to end the Gaza war succeed in lifting a blockade of the territory, Gazans will not see any improvement in their lives for at least another 15 years, the head of a U.N. relief agency said on Monday.

"The question will be, is it a ceasefire that brings us simply back to the pre-existing condition under the blockade?" Pierre Krahenbuhl, the head of the United Nations Relief and Works Agency (UNRWA), said in an interview.

"If that is the case, it will take years and years and years to rebuild," he said, emphasizing the length of time it takes to get building materials, construction equipment and other goods across the Zionist and Egyptian borders into the territory.

"With the extent of destruction that has taken place, you cannot really imagine that we would achieve anything before 15 years or more," unless the pace of importing goods changes.

The Zionist and Egyptian officials have indicated a willingness to loosen the blockade as long as the Palestinian Authority takes over administration of the borders from Hamas.

But the Zionist entity rejects any wholesale lifting of border restrictions, claiming some building materials that entered Gaza in recent years were used by Hamas to build reinforced tunnels.

Occupation authorities also want the demilitarization of Gaza, a move backed by the European Union and others but one that Hamas has said it is not prepared to take.

While UNRWA could provide emergency assistance, bold steps were needed if the territory is to be able to stand on its own feet, Krahenbuhl said. "There is no actor who can resolve this alone if we go back to the pre-existing conditions under occupation and blockade," he added.

"If this does not change, if that paradigm does not change, if there is not something that brings a new paradigm, a new deal, new hope for the people in terms of opening up," then Gaza would be consigned to "incredible difficulties" he said.

UNRWA has been working in the region since 1949, originally helping refugees from the war that ensued from the foundation of Zionist entity in 1948. One of its main responsibilities now is running schools and clinics throughout Gaza.