Turkey has been one of the most outspoken critics of U.S. President Donald Trump’s decision to label Jerusalem the Israeli capital and move the U.S. Embassy there.

Speaking at a meeting of the ruling Justice and Development (AK) Party in Sivas, central Turkey, Erdogan said: “Trump’s declaration of Jerusalem as the capital of Israel is null and void for us in any case.

“Declaring it as a capital and relocating the embassy has no validity for us.”

Erdogan has called an extraordinary summit of the Organization of Islamic Cooperation on Wednesday in Istanbul.

The president said it would draw up a roadmap for Muslim countries to follow as they opposed the U.S. decision. He added that Turkey would oppose the plan within international law and democratic principles.

Later, Erdogan told an audience at an opening ceremony in Sivas that Israel was a “terrorist” state.

“Palestine has been under occupation since 1947,” he said. “Israel is an occupying state, a terrorist state.”

He added that the U.S. declaration was an attempt to damage peace and security in the region. Erdogan also said the decision ignored a 1980 UN Security Council resolution signed by the U.S. that condemned the Israeli annexation of Jerusalem.

Resolution 478 called on member states to withdraw diplomatic missions from Jerusalem and described East Jerusalem as “under occupation”.

Anadolu Agency