Turkish President Recep Tayyip Erdogan on Friday blasted several Arab countries for backing a Middle East peace plan unveiled by the United States, condemning it as "treason."

"Some Arab countries that support such a plan commit treason against Jerusalem, as well as against their own people, and more importantly against all humanity," Erdogan told his party's provincial heads in Ankara.

Erdogan, a strong advocate of Palestinian rights, singled out Saudi Arabia, the United Arab Emirates, Bahrain and Oman.

"Saudi Arabia in particular, you are silent. When will you break your silence? You look at Oman, Bahrain, and Abu Dhabi is the same," said the Turkish president.

"Shame on you! Shame on you! How will those hands that applaud (the plan) give an account of this treacherous step?"

Turkey's relations with Riyadh and Abu Dhabi deteriorated after the 2018 murder of Saudi journalist Jamal Khashoggi in the kingdom's consulate in Istanbul.

Ankara has repeatedly claimed the Washington Post columnist was killed on the order of the Saudi leadership, which has denied involvement.

On the conflict that engulfs Libya, Turkey supports the UN-recognised government in Tripoli while Saudi Arabia and the United Arab Emirates back eastern commander Khalifa Haftar, who controls three-quarters of Libyan territory.

US President Donald Trump on Tuesday unveiled the details of the plan, saying that Jerusalem would remain Israel's "undivided capital".

The so-called peace plan unilaterally annuls previous UN resolutions on the Palestinian issue and suggests giving Israel almost everything they have been demanding.

Former US president Jimmy Carter has called Trump plan illegal and urged the United States to act to stop its implementation.

Jerusalem is already a source of friction in relations between Turkey and the United States, which recognised the city as Israel's capital in 2017 and moved the embassy there.

"We never recognise and accept this plan that usurps Jerusalem entirely," Erdogan said, slamming it as a "disgraceful" scheme.

"Jerusalem cannot be left to the bloody claw of Israel," he added.

Erdogan warned that everyone would be responsible for "grave consequences" of any step that encourages Israel, which he called a "rogue state" and a "terror state."

The Turkish leader also said he would speak with Palestinian president Mahmud Abbas and Hamas leader Ismail Haniyeh.

Earlier on Thursday, the Turkish president said the so-called Middle East peace plan is an “occupation project”.

“Jerusalem is not for sale, he said while speaking at the 5th Anatolian Media Awards ceremony in the capital Ankara.

Condemning the so-called “Deal of the Century”, the president said, “Jerusalem is a red line for us.”

On Tuesday, US President Donald Trump released his plan to end the Israeli-Palestinian dispute at the White House alongside Netanyahu, with no Palestinian officials present.

During the event, Trump referred to Jerusalem as “Israel’s undivided capital.”