A major nemesis during the Iraq War is warning that if the U.S. moves its embassy in Israel from Tel Aviv to Jerusalem, as President Trump has vowed, it will be regarded as a declaration of war against Islam.

Iraqi cleric Moqtada al-Sadr, who led a militia against U.S.-led coalition forces in Iraq, called for the "formation of a special division to liberate Jerusalem were the decision to be implemented."

Although Congress passed a law two decades ago directing that the embassy be moved to Jerusalem, every president has signed a waiver every six months, citing national security concerns. The U.S. largely has fallen in line with United Nations policy, which does not recognize Israel's annexation of east Jerusalem after the city's capture in the Arab-initiated Six Day War.

The Palestinians view east Jerusalem as the third holiest city in Islam and the future capital of a Palestinian state.

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Commenting on Sader's declaration, Islam expert Robert Spencer, the publisher of Jihad Watch, observed that while Western policy analysts routinely treat Israel's conflict with the Arabs as a matter of a land dispute that can be settled by negotiations, Muslim spokesmen worldwide treat it as an Islamic matter.

"Al-Sadr and many others are trying to make this move of the embassy into a showdown," Spencer wrote. "They are trying to make President Trump back down, which would set an extremely damaging precedent.

He warned that "if the administration backs down and the showdown is averted, those analysts would be kidding themselves if they didn’t realize that it is coming sooner or later anyway."

Caroline Glick, a former assistant foreign policy adviser to Israeli Prime Minister Benjamin Netayahu, wrote in December that there "is no single step the U.S. can take that will do more to rebuild U.S. credibility as an ally than moving the embassy to Jerusalem."

"By taking the step that none of his predecessors would take to stand in support of the U.S.’s most embattled ally worldwide, Trump will show that America can again be trusted," said Glick, author of "The Israeli Solution: A One-State Plan for Peace in the Middle East." "And moving the embassy will accomplish this goal without placing one U.S. soldier at risk, and will cost U.S. taxpayers no more than a few million dollars for construction and moving fees."

Sadr, meanwhile, said the Arab League and the 57-member Organisation of Islamic Cooperation should take a decisive stand on the embassy issue or dissolve themselves, Agence France-Presse reported.

Sader also called for the immediate closure of the U.S. Embassy in Iraq should Washington transfer its embassy in Israel.

Palestinian Authority President Mahmoud Abbas has said that if the U.S Embassy moves, he could revoke the PLO’s recognition of Israel. His Fatah party, formerly led by Yasser Arafat, warned the move “would open the gates of hell.”

Abbas has asked leaders such as Russian President Vladimir Putin and Jordan's King Abdullah to help pressure Trump to change his mind.

'True friend of Israel'

While Trump promised during his presidential campaign that moving the embassy would happen "very quickly" if he were elected, White House press secretary Sean Spicer said Monday that no decision had been made.

"We're at the very early stages of that decision-making process," Spicer told reporters.

Spicer later said, CNN reported, that the Trump administration was going to "continue to consult with stakeholders as we get there."

Jerusalem Mayor Nir Barkat said Monday he is in talks with White House officials about fulfilling Trump's pledge, the Jerusalem Post reported.

“Trump has proven that he is a true friend of the state of Israel, and keeps his promises," the mayor said in a statement.

“We’ll help the U.S. government use its authority [and provide] all the necessary assistance to make the [relocation] of the embassy to Jerusalem as quick and smooth as possible,” he said.

Barkat told Israel's Army Radio that he believes it is just a matter of time until the relocation takes place.

“I am holding talks with government officials in the U.S., and I know that they are serious about their intention,” he said.

Barkat noted the U.S. has various properties in Jerusalem that could serve as a solution.

The U.S. Embassy in Israel has always been in Tel Aviv. The ambassador's residence is in Herzliya Pituach, about 30 minutes north.

It's been suggested that Trump's ambassador to Israel – he has nominated attorney David Friedman – could work out of an existing U.S. consulate in Jerusalem, which would become the de facto embassy.

Law to move embassy never implemented

To move the embassy, Trump would only need to allow the 1995 Jerusalem Embassy Act to take effect.

Passed 93-5 in the Senate and 374-37 in the House, it declares, "Jerusalem should be recognized as the capital of the State of Israel," and the U.S. Embassy should be established there "no later than May 31, 1999."

The law, however, was never implemented, because Presidents Clinton, Bush and Obama signed a waiver every six months claiming it is in the security interest of the United States to keep the embassy in Tel Aviv.

Clinton and Bush also vowed during their campaigns to move the embassy but backed off.

Obama renewed the presidential waiver in December. It expires at the beginning of June. Whether or not Trump could override the waiver is unclear.

The gripping TV series "Against All Odds" tells modern Israel's miraculous story from the viewpoint of an investigative journalist. The DVD set is available now at the WND Superstore!