(AP) AMMAN- Jordan’s government spokesman warned on Thursday of “catastrophic” repercussions if President-elect Donald Trump makes good on a campaign promise to move the US Embassy in Israel to Jerusalem.

Such a move could affect relations between the US and regional allies, including Jordan, Information Minister Mohammed Momani told The Associated Press, addressing the issue publicly for the first time.

An embassy move would be a “red line” for Jordan, would “inflame the Islamic and Arab streets” and serve as a “gift to extremists,” he said, adding that Jordan would use all possible political and diplomatic means to try and prevent such a decision.

The US considers pro-Western Jordan as an important ally in a turbulent Mideast. The Hashemite kingdom is a key member of a US-led military coalition against ISIS in neighboring Syria and Iraq, and maintains discreet security ties with Israel.

Jordan also has a stake in Jerusalem, serving as custodian of Islam’s third holiest shrine in the city’s eastern sector.

Israel captured east Jerusalem from Jordan in 1967 and annexed it to its capital. It is the home of the holiest site for Jews – the Western Wall.

Momani, the Jordanian minister, said that moving the US Embassy to Jerusalem “will have catastrophic implications on several levels, including the regional situation.” He said countries in the region would likely “think about different things and steps they should take in order to stop this from happening.”

“It will definitely affect the bilateral relationship between countries in the region, including Jordan, and the parties that will be related to such a decision,” he said.

Last month, Trump adviser Kellyanne Conway was quoted as saying that moving the embassy to Jerusalem is a “very big priority” for the president-elect.

Trump’s choice for US ambassador in Israel, David Friedman, has said he looks forward to working from Jerusalem.

The Palestinians want to establish the capital of a future state, and various UN resolutions have negated or ignored Jewish history in the city.

Most countries, including the United States, maintain their embassies in Tel Aviv.