The E.U.’s decision to blacklist the military wing of Hezbollah comes after years of urging from the U.S. and Israel. (RAMZI HAIDAR/AFP/GETTY IMAGES)

The European Union on Monday declared the military wing of Hezbollah a terrorist organization, a move designed to pressure the Shiite political and militant group across a region that has long been an important base for fundraising and support.

The unanimous decision by foreign ministers of the 28-nation E.U., which comes after years of urging from the United States and Israel, will place travel restrictions on members of the military wing of Hezbollah and will freeze E.U. assets associated with that part of the group.

But there were no immediate details of how the restrictions will be implemented. Hezbollah does not actually organize itself into political and military wings, and critics of the decision said that in practical terms, Europe’s desire to maintain contact with politicians within the organization would limit the reach of Monday’s decision.

The E.U. declaration comes at a time when Hezbollah has significantly escalated its backing for Syrian President Bashar al-Assad in the sectarian civil war in that country and has increased its efforts to carry out attacks on Israelis and Iranian-chosen targets around the world, according to assessments by U.S. intelligence officials.

“It is good that the E.U. has decided to call Hezbollah what it is: a terrorist organization,” said Dutch Foreign Minister Frans Timmermans in a statement. The move will have the effect of “limiting its capacity to act,” he said.

But Iran-backed Hezbollah is also one of Lebanon’s most powerful political forces. Some European countries had previously resisted the terrorist designation, fearful that such an action by the E.U. would lessen Europe’s influence in Lebanon’s fragile political system. Hezbollah has dominated Lebanon’s parliament since 2011.

White House spokesman Jay Carney said the Obama administration welcomes the E.U. designation, which he said would have “a significant impact on Hezbollah’s ability to operate freely in Europe by enabling European law enforcement agencies to crack down on Hezbollah’s fundraising, logistical activity, and terrorist plotting on European soil.”

Europe, with its long history of immigration from and cultural ties to Lebanon, has been fertile ground for Hezbollah to do fundraising and outreach. France, bound by history and language to Lebanon, has a large Lebanese Shiite community. And Germany’s domestic intelligence agency estimated in 2011 that there were 950 Hezbollah supporters living within its borders.

Hezbollah and its allies in Lebanon immediately condemned the move.

The E.U. decision is “hostile and unjust and not based on justification or evidence,” Hezbollah said in a statement late Monday on the Web site of al-Manar, its media wing. Hezbollah blamed the the United States for pushing Europe to act.

The country’s Hezbollah-backed caretaker Prime Minister Najib Mikati said that he hoped that the decision would be reconsidered after “a second careful read of the facts.”

The Hezbollah-aligned Tawhid Party said Europe’s decision was forced by American pressure.

“Hezbollah is not a terrorist organization, as claimed by these countries, but a resistance movement that defends pride and human dignity in the face of Israeli aggression,” it said in a statement carried by the state-run National News Agency. Hezbollah leader Hassan Nasrallah had previously dismissed attempts to label the organization as a terrorist organization as symbolic.

The decision to sanction the group’s military wing might be difficult to implement, analysts said, because of the complexity of separating political activities that Europe deems legitimate from military activities that it does not — a distinction Hezbollah does not make.

“It’s a symbolic step,” said Guido Steinberg, an expert on Islamic radicalism at the German Institute for International and Security Affairs in Berlin. “It might change their behavior to some extent within Europe, but it won’t change their position in Lebanon,” where they receive significant funding from Iran, he said.

The E.U.’s “military wing” distinction will allow Europe to carry on diplomatic relations with Hezbollah politicians inside Lebanon, unlike the United States, which has added the entire Hezbollah organization to its terrorist list.

Pressure to add the military wing to the terrorist list increased after Hezbollah ramped up its involvement in Syria’s civil war, analysts and officials said. The group’s support for Assad has helped him make important military advances in recent months, putting rebel groups under pressure.

“The E.U. has sent a clear message that it stands united against terrorism,” British Foreign Secretary William Hague said Monday. Britain had pushed for the move and has listed the military wing of Hezbollah as a terrorist organization since 2008.

“It shows that no organization can carry out terrorist acts on European soil…without facing the consequences,” Hague said, adding that the broader European move was inspired by evidence that Hezbollah was involved in the bombing of a bus of Israeli tourists in Burgas, Bulgaria, last year that killed seven people.

The move came after an E.U. decision last week to forbid the European Commission from funding Israeli entities in the West Bank on land that Palestinians claim for a future state. Monday’s decision on Hezbollah may help mend fences between European countries and Israel, some Israeli officials said.

Even as they applauded the designation, however, many Israeli leaders wondered aloud why it took European ministers so long and said the decision should also apply to Hezbollah’s political wing.

“We make no distinction between the political and military activities of Hezbollah,” Israeli Deputy Foreign Minister Zeev Elkin said in an interview. “The group has been responsible for many acts of terror in Europe and elsewhere.”

Prime Minister Benjamin Netanyahu called Hezbollah “a terror group of the Iranian regime, a terror group that has carried out attacks around the organization with no difference between different wings.

In 2006, Israel and paramilitary units from Hezbollah fought a 34-day war across the Israel-Lebanon border and in the Golan Heights, which Israel has controlled since 1967. Currently, Israeli intelligence reports say, Hezbollah has tens of thousands of rockets in southern Lebanon, ready to fire at the Jewish state. In recent months, Israeli airstrikes have hit targets in Syria in what Israel says is an effort to stop Syria and Iran from transferring sophisticated weapons to Hezbollah.

Eglash reported from Jerusalem. William Booth in Jerusalem and Loveday Morris in Beirut contributed to this report.