Israeli officials on Thursday unanimously accused Iran and Lebanese group Hezbollah of carrying out a deadly attack against Israelis in Bulgaria, setting the stage for new tensions in the Middle East.
But observers said Israel was unlikely to respond to the incident by attacking Iran or Lebanon, and would instead weigh a diplomatic response.
The bombing of a bus at Burgas airport on the Black Sea killed five Israeli tourists and injured more than 30, Israel's foreign ministry said in what was the deadliest attack on Israelis abroad since 2004.
Israeli Prime Minister Benjamin Netanyahu immediately pointed the finger at Iran.
"All the signs point to Iran," he said in a statement on Wednesday evening, linking the blast to a string of attempts to attack Israelis around the world.
"Israel will respond forcefully to Iranian terror."
The Israeli premier later repeated the accusation in a conversation with US President Barak Obama, warning: "Iran is a state of global terror. It must bear the consequences of that."
On Thursday morning, Israel's Defence Minister Ehud Barak told Israeli public radio that Israel was "facing a global wave of terror."
"The attack in Burgas was led by members of Hezbollah and sponsored by Iran," he said.
Barak said Israel's intelligence services were working with partners overseas to share information about potential attacks.
"There are often very big successes, but it doesn't always work," he said. "We will do everything possible to track down the perpetrators and instigators of the Burgas attack and punish them."
Also speaking to public radio on Thursday, Foreign Minister Avigdor Lieberman said Iran's elite Revolutionary Guards was involved in the attack.
"It's Hezbollah helped by the Iranian Revolutionary Guard that is responsible for this suicide attack. This is proven information," he said, indicating that Israel was facing a "global terrorist war financed and organised by Iran."
Lieberman's deputy Danny Ayalon, called for the European Union to "add the bloodthirsty Hezbollah to its list of terrorist organisations."
But he also said Israel would submit a complaint to the United Nations Security Council and would "avoid reacting in a hot-headed manner, and carefully consider its response because all the pieces of the puzzle must be put in place."
Wednesday's explosion comes after a series of attempts to hit Israelis abroad, many of which have been blamed on Iran.
In mid February, Israeli embassy staff in India and Georgia were targeted in two bomb attacks shortly before a string of botched blasts in Bangkok also targeting Israeli diplomats.
In March, Azerbaijan arrested 22 people on suspicion of plotting attacks on the US and Israeli embassies in Baku on behalf of Iran.
And earlier this month, Cypriot police arrested a Lebanese national on suspicion he was planning to attack Israelis.
The Black Sea bombing took place on the 18th anniversary of a 1994 attack on a Jewish community centre in Buenos Aires that killed 85 people and wounded around 300, which Israel also blamed on Iran.
Despite the public accusations against Iran and Hezbollah, Israeli analysts said a military response from Israel was unlikely in the short-term.
"If anyone expects a strong Israeli response... they are going too far," wrote Ofer Shelah in the Maariv daily.
"Israel’s response will be diplomatic in nature and will describe Iran’s map of terror attacks and attempted terror attacks with the goal of persuading all those who still doubt that Iran is a serial exporter of terrorism," he wrote.
"Ideas of revenge, collective or individual, will have to wait."
Writing in Israel Hayom, analyst Yoav Limor agreed, saying there were "no question marks" about the perpetrators of the attack, but that Israel would hold off an immediate response.
"All the experts said last night that Hezbollah was responsible," he wrote.
But Israel would find it "hard to respond," he said, indicating that military action against Iran would only occur in the context of its nuclear activities, and against Hezbollah if the group managed to get hold of chemical weapons from Syria.