UNESCO's executive board has passed a resolution that criticises Israel's actions in occupied Jerusalem and the Gaza Strip, with Palestinian leaders hailing the move as a "step forward" and a "victory for international law".

The resolution, which describes Jerusalem as "occupied" and declares Israel's sovereignty over the city "null and void", was backed by 22 countries, a UNESCO spokesman said on Tuesday.

The United States, Germany, Italy and seven other board members voted against it.

Palestinian Foreign Minister Riyad Malki welcomed the result of the vote, saying that the world had chosen to "stand on the side of what is right in the face of [Israel's] injustice, occupation and its illegitimate policies.

"We will defend our heritage and culture, our past and our future," Malki said.

"We will face all the campaigns of distortion and destruction led by the Israeli occupation authority, armed with international law and the will of our Palestinian people who are capable of creating a future free from occupation."

The resolution was submitted by Algeria, Egypt, Lebanon, Morocco, Oman, Qatar and Sudan.

It calls on Israel, as the "occupying power", to cease "persistent excavations, tunnelling, works and projects in East Jerusalem", which the Palestinians want as the capital of their future state.

It reaffirms "the importance of the Old City of Jerusalem and its walls for the three monotheistic religions", while accusing Israel of taking actions that have "altered, or purport to alter the character and status of the Holy City".

The resolution, which has softer wording than another UNESCO decision last year, also criticises Israel for its blockade on the Hamas-run Gaza Strip.

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The Israeli foreign ministry, which called the resolution an "unnecessary politicisation of UNESCO", had started ramping up its criticisms of the UN body well before Tuesday's vote.

"The proposed resolution will not affect our determination to operate in Jerusalem," it said on Thursday. "It will, however, impair UNESCO's deteriorating status and relevance."

The executive board decision now goes to the plenary, which will consider the issue on Friday, UNESCO spokesman Roni Amelan said.

"We understand very well that we are struggling against a huge power supported by many countries, including the US. And we know that our success will be cumulative - step by step, stone by stone," Mustafa Barghouti, leader of the Palestinian National Initiative, told Al Jazeera.

"We know it won't change the reality on the ground immediately, but this is certainly one step forward."

In 2011, the Palestinians were admitted as a member state of UNESCO, which led the US to suspend its payments to the organisation.

Israel's occupation of the West Bank, including East Jerusalem, and the besieged Gaza Strip, is considered illegal under international law.

More than half-a-million Israelis live in Jewish-only settlements across the occupied West Bank, including East Jerusalem, according to the Israeli rights group B'Tselem.

On the watch of Benjamin Netanyahu, the Israeli prime minister, settlements expanded an estimated 23 percent between 2009 and 2014.