Some 35 aid groups from around the world, including ActionAid and Oxfam, launched a joint call Wednesday to end Israel's blockade of the Gaza Strip, which is in dire need of reconstruction.
Last summer's devastating war in Gaza caused mass casualties, killing 2,251 Palestinians, including more than 500 children. Seventy-three people were killed on the Israeli side, including 67 soldiers.
"For a whole year the Israeli government has restricted basic and essential construction materials from entering Gaza," said a statement signed by the NGOs and posted on the site of activist group Avaaz.
"Not one of the 19,000 homes that were bombed and destroyed has been fully rebuilt.
"One year on, around 100,000 Palestinians in Gaza are still homeless, hospitals and schools still lie in ruins, and whole neighbourhoods have no access to running water."
It controls the waters around Gaza and residents are not allowed to travel more than six nautical miles from the coast.
Land crossings are also strictly controlled by Israel, which says its blockade is essential to prevent militants from obtaining materials to fortify military positions and build rockets they could fire at the Jewish state.
"Just five percent of the 6.7 million tonnes of steel bars, cement and aggregates needed to rebuild what was destroyed since the end of the war has been permitted to enter Gaza," the statement said.
"At this rate, it could take 17 years before Gaza is rebuilt."
The NGOs acknowledged that Palestinian political parties had failed to reconcile and prioritise reconstruction, "and Egypt's closure of its border has further limited supplies entering Gaza".
But they said Israel's blockade was the main obstacle to reconstruction.
A petition launched by the NGOs has so far garnered more than 450,000 signatures from around the world.