The foreign ministers of France and Germany say they will hold on to the nuclear agreement with Iran, regardless of the upcoming US decision on whether to nix the deal.
"The Europeans' decision allows us to prevent Iran from immediately restarting their (nuclear) activities and to avoid escalating tensions", he said. "Don't be weak", he said.
Europe can no longer count on the military protection of the United States and should "take their destiny into their own hands", said German Chancellor Angela Merkel, reports Bloomberg.
"What's most important is to maintain stability and peace in the Near and Middle East", he stressed.
While Iran's arch foes Israel and Saudi Arabia welcomed Trump's decision, other signatories to the existing deal - Russia, China and the European Union - vowed to stick by it.
"We come from different political pasts, but we find common ground, and that is the magic of Europe", she said.
Her party has also firmly slapped down the proposal of a finance minister for the bloc.
Macron will make a speech later Thursday, his fourth major address on the continent's future, already murky given Britain's looming exit from the European Union and a surge in nationalist movements.
He also took aim at the Germans over their reluctance to spend, as well as their wariness of any plan that potentially draw resources from richer countries to help out struggling ones. "Other powers. haven't kept their word", Macron said, without naming a country directly.
But it is now time for "Germany to draw up its response by June" on proposed European reforms, Macron said.
The Middle East was becoming very risky, said French Foreign Minister Jean-Yves Le Drian, adding that there was no "Plan B" in response to Trump's move and that France wanted to keep the accord alive even without Washington on board.
Washington has already warned that European companies will be subject to fresh sanctions against Tehran, setting a six-month deadline to end any business in Iran or risk heavy penalties.