French Foreign Minister Jean-Marc Ayrault warned Sunday that moving the US Embassy in Israel from Tel Aviv to Jerusalem would result in “extremely serious consequences.”

Speaking as representatives from 70 countries gathered in Paris to try to revive Israeli-Palestinian peace efforts, Ayrault told French TV he believed US President-elect Donald Trump would find it “impossible” to fulfill the pledge he made during his campaign to transfer the embassy.

“When you are president of the United States, you cannot take such a stubborn and such a unilateral view on this issue. You have to try to create the conditions for peace,” Ayrault said.

Trump hasn’t yet laid out a clear Mideast policy, but has signaled he will be more sympathetic to Israel’s hard-line right than previous US administrations.

Trump and his incoming administration have spoken repeatedly of his intention to relocate the embassy to Israel’s capital, leading to wall-to-wall condemnations and warnings of a violent outburst from Palestinian leaders, the Jordanian government and outgoing US Secretary of State John Kerry.

Palestinian officials have warned that the move, which could symbolize recognizing Jerusalem as Israel’s capital, would inflame tensions in the Middle East and sink peace efforts.

On Friday, Abbas told French newspaper Le Figaro that the PLO would consider revoking its recognition of Israel if Trump follows through with moving the embassy.

The Palestinians regard East Jerusalem as the capital of their future state, while Israel proclaims the entire city as its capital.

The city’s status is one of the thorniest issues of the decades-long Israeli-Palestinian conflict.

Israel in the 1967 Six Day War captured the West Bank and East Jerusalem, which had been held by Jordan since 1948. It later annexed East Jerusalem but the move was never recognized by the international community.