United Nations, September 11 (RHC)-- Palestinian and regional leaders have sharply denounced Israeli Prime Minister Benjamin Netanyahu's pledge to annex large parts of the occupied West Bank if he wins next week's snap election.

Netanyahu, who is fighting for his political life after an inconclusive vote in April, said on Tuesday Israel will "apply Israeli sovereignty to the Jordan Valley and the northern Dead Sea immediately" if he secured a fifth term in the September 17 polls.

The Jordan Valley and the northern Dead Sea make up 30 percent of the West Bank. They lie in Area C, which means they are mostly under Israeli military and civil control.  Approximately 65,000 Palestinians and 11,000 Israelis residing in illegal settlements live in that area, according to Israeli human rights group B'Tselem.  The main Palestinian city is Jericho, with about 28 villages and smaller Bedouin communities.

After Netanyahu's announcement, Arab foreign ministers meeting in Cairo called his election promise a "dangerous development and a new Israeli aggression by declaring the intention to violate the international law."

"The Arab League regards these statements as undermining the chances of any progress in the peace process and will torpedo all its foundations."  In a series of separate statements, Qatar criticised "Israel's continued contempt of international law"; Turkey slammed the annexation pledge as "racist"; Jordan called Netanyahu's plan a "serious escalation"; and Saudi Arabia called for an emergency meeting of the Organisation of Islamic Cooperation (OIC).

The United Nations, meanwhile, warned that Netanyahu's plan would have "no international legal effect."

During his televised announcement, Netanyahu also reaffirmed a pledge to annex all of the Jewish-only settlements Israel has established in the West Bank.

Some 650,000 Israeli Jews currently live in more than 100 settlements built since 1967. International law views both the West Bank and East Jerusalem as "occupied territories" and considers all Jewish settlement-building activity there as illegal.

Palestinians swiftly reacted to Netanyahu's statements by saying he was destroying any hopes of peace.   Mahmoud Abbas, president of the Palestinian Authority, warned that all agreements signed with Israel would end if it annexed parts of the West Bank, noting that Netanyahu's announcement contradicts UN resolutions and international law.

Hanan Ashrawi, a senior official in the Palestine Liberation Organization (PLO), wrote on Twitter that Netanyahu was seeking to impose a "greater Israel on all of historical Palestine and [carry] out an ethnic cleansing agenda".

"This announcement is a declaration of war against the Palestinian people's rights as well as the very foundations of the international rules-based order," she said in a separate statement.

In his address, Netanyahu also said a long-awaited United States peace plan, the release of which has been delayed until after the election, represented "a historic and unique opportunity to apply our sovereignty over our settlements" in the West Bank and "other places key to our security, our heritage and our future".

White House senior adviser Jared Kushner said in early May that he hoped Israel would take a hard look at President Donald Trump's upcoming proposal before "proceeding with any plan" to annex West Bank settlements.

Abdulsattar Qassim, a political science professor at al-Najah University in Nablus, said Palestinians are not expecting anything from Trump, a staunch Netanyahu ally who has enacted a series of policies that support Israel's expansion, including the widely condemned decision to recognise Jerusalem as Israel's capital.

"From the way Trump has been behaving, we expect that he will support any kind of Israeli decision to annex parts of the West Bank," Qassem told Al Jazeera.

"Trump has shown great animosity towards the Palestinians. He has transferred the US embassy to Jerusalem, supported the annexation of the occupied Golan Heights, and cut the financial resources of UNRWA, the Palestine Liberation Organization and the PA."

According to Qassem, Netanyahu's pledge to annex occupied Palestinian territories is hardly new within the arena of Israeli politics.

"This project is not exclusive to Netanyahu," he said.  "All across the Israeli political spectrum, from Labour to the right-wing Likud party, Israelis have favoured the annexation of the West Bank."