BRUSSELS (Reuters) - President Donald Trump’s tough stance on Iran, new tariffs on European Union metal imports and U.S. demands for higher defense spending in Europe are part of a strategy to strengthen the West, a senior U.S. official said on Thursday.

FILE PHOTO: U.S. Assistant Secretary of State for European and Eurasian Affairs Wess Mitchell speaks during a news briefing following his meeting with Ukrainian President Petro Poroshenko in Kiev, Ukraine May 2, 2018. REUTERS/Valentyn Ogirenko

Wess Mitchell, U.S. Assistant Secretary of State for European and Eurasian Affairs, said that without such actions, U.S. and European diplomatic and military leadership would be overtaken by China, Russia and Iran.

“Taking strong positions on these issues may not always lead to immediate agreement. But the long term costs of neglecting these things far outweigh political unity,” Mitchell told European and NATO officials, in a rare speech by a Trump administration official in Brussels.

European leaders are deeply worried by Trump’s foreign policy and his “America first” rhetoric, while his May 8 decision to withdraw from the Iran nuclear deal undermined an agreement prized by Europeans.

A Group of Seven summit in Canada earlier this month laid bare tensions between NATO allies after Trump’s decision to impose tariffs on steel and aluminum imports from the European Union and Canada on national security grounds.

Mitchell, who studied in Berlin and speaks German, sought to place Trump’s decisions into a coherent policy plan that would benefit European countries because Trump was acting decisively to bring change, rather than relying on endless negotiations.

“In all of these areas, with Iran, defense spending, trade, we are committed to finding a common way forward, we are committing to acting. We can debate, we can strategize, we can coordinate, but we must act,” he said.

“In the actions we take, we are hoping to spur a multilateral response to address some of the world’s toughest challenges,” Mitchell said at the Carnegie Europe think-tank gathering in Brussels.

Mitchell said U.S. import tariffs on European goods would end “structural trade imbalances and predatory trade practices” in U.S.-EU trade, which would weaken the West if they continue.

Reimposing sanctions on Iran by withdrawing from the Iran nuclear accord would help stop Tehran’s missile program and limit the regional reach of Iran’s Revolutionary Guard, he said.

Mitchell also repeated Trump’s central message to NATO that European allies must spend 2 percent of economic output a year on defense to rebuild “atrophied European militaries.”

Trump is expected at a NATO summit in Brussels in July, a year since he first came to the alliance and publicly admonished allies for not spending enough on defense.

Many EU and NATO diplomats now view the U.S. president as an unknown quantity with a lack of interest in the transatlantic ties that Europe and Canada cherish, and who is unnecessarily stoking a global trade war that will hurt economic growth.