PARIS, May 23 (Xinhua) -- French Foreign Minister Jean-Yves Le Drian warned Wednesday that the United States' tough stance on Iran had fuelled "serious tension" and risked triggering a war in the region.

"We are in a situation of a major instability...All the conditions are met for a conflagration," Le Drian said.

The French diplomat told France Inter radio in an interview that Washington's posture "risks endangering the region more".

Earlier this week, U.S. Secretary of State Mike Pompeo threatened to impose "the strongest sanctions in history" on Iran if it refused to curb its ballistic missile program and its regional influence.

But Le Drian said: "we disagree with the method because this collection of sanctions, which will be set up against Iran, will not enable dialogue and, on the contrary, it will reinforce the conservatives and weaken President (Hassan) Rouhani."

"These sanctions are not acceptable. We can't allow them to become legitimate," he added.

Le Drian said the Iran nuclear deal was "an asset that must be maintained".

The Iran nuclear deal, formally called the Joint Comprehensive Plan of Action, was signed in July 2015 by Iran and the five permanent members of the United Nations Security Council -- Britain, China, France, Russia and the United States -- plus the European Union (EU) and Germany.

Under the deal, Iran agreed to freeze its nuclear programs in return for the lifting of most international sanctions.

U.S. President Donald Trump decided to withdraw from the agreement struck under his predecessor Barack Obama's administration, as he said it did not address Iran's ballistic missile program, its nuclear activities beyond 2025 or its role in conflicts in Yemen and Syria.

According to the International Atomic Energy Agency (IAEA) in Vienna, however, Iran has so far complied with all of the conditions established under the deal.