RAMSTEIN, Germany (AFP) - The State Department will immediately act on President Donald Trump's order to prepare to relocate the American embassy in Israel from Tel Aviv to Jerusalem, Secretary of State Rex Tillerson said on Wednesday (Dec 6).

"The State Department will immediately begin the process to implement this decision by starting the preparations to move the US Embassy from Tel Aviv to Jerusalem," Tillerson said in a statement shortly after Trump's landmark announcement.

Trump decision to recognise Jerusalem as the capital of Israel has sparked warnings that it could unleash more violence in the Middle East and Tillerson said his department had taken measures to protect American nationals in the region.

"The safety of Americans is the State Department's highest priority, and in concert with other federal agencies, we've implemented robust security plans to protect the safety of Americans in affected regions," said Tillerson, who is on a visit to Germany.

Although Trump's decision has been met with widespread criticism in the region, the top US diplomat said that the US president had only acted after widespread consultation with allies.

"We have consulted with many friends, partners, and allies in advance of the President making his decision," he said.

"We firmly believe there is an opportunity for a lasting peace," he added.