German Foreign Minister Heiko Maas warns that strains between Iran and the United States have "reached a fever pitch", calling on European powers to take a lead in negotiations to help resolve the situation.

"There is a clear danger of miscalculations, misunderstandings, provocations leading to unforeseeable consequences in this highly tense region," Maas warned upon arrival in the Iraqi capital, Baghdad, on Saturday.

Tensions between Washington and Tehran have been rising since US President Donald Trump withdrew the US from a 2015 international nuclear deal and imposed unilateral economic sanctions against Iran, mainly targeting its energy dealings on the global market.

In early May, the Trump administration beefed up the US’s military presence in the Persian Gulf, citing alleged and unspecified threats posed by the Islamic Republic to American troops and interests.

The US’s recent deployment of an aircraft carrier, B-52 bombers and Patriot missiles to the Middle East has raised fears that the Trump administration was contemplating military aggression against Iran.

Iran has insisted that it will not initiate any conflict, but will firmly defend the country against any act of aggression.

"The latest escalation requires us as European neighbors to intervene in favor of de-escalation and peaceful co-existence," the top German diplomat said.

"We cannot just seek dialogue, we must lead it, precisely where the differences seem insurmountable and long-simmering conflicts run deep," he said.

Maas also said that Europe was determined to preserve the 2015 nuclear deal with Iran, describing the accord as a "key factor for stability and security in the region."

"We Europeans are convinced that it is worth every effort to work toward upholding the Vienna nuclear agreement with Iran."

The German foreign minister further praised Baghdad's "measured" approach and mediating role in defusing tensions in the region, urging countries not to abandon Iraq.

"We cannot abandon Iraq now," he said, after holding talks with Iraqi Prime Minister Adil Abdul-Mahdi and President Barham Salih, pledging to continue supporting Iraq's rebuilding effort.

Germany to continue operations in Iraq

Maas also said Germany, a member of the US-led coalition purportedly fighting the Daesh Takfiri terrorist group, would continue to participate in the mission to combat the terror group.

He further warned that the terrorist group, which has been defeated in the Arab country, could rebuild structures "underground," a reality that "we can and must prevent."

The German top diplomat arrived in Baghdad on Saturday as part of a wider trip to the Middle East seeking to de-escalate tensions between Iran and the United States. Maas's visit was not announced ahead of time for security reasons.

Maas was in Jordan on Friday for the first stop of his high-profile four-day Middle East tour.

Maas is expected to arrive in Iran on Monday to hold talks with his Iranian counterpart Mohammad Javad Zarif.

The German foreign minister reportedly coordinated his trip with the UK and France and informed US Secretary of State Mike Pompeo of the trip when the US diplomat was in Berlin last week.

Jens Ploetner, a political director in the German Foreign Ministry, reportedly traveled from Berlin to Tehran two weeks ago to lay the groundwork for Monday's meeting, according to German media.

Maas's four-day Middle East trip will also include the United Arab Emirates (UAE).