Hizbullah flag
Hizbullah flagIsrael news photo: Flash 90

Bulgaria’s foreign minister said Wednesday that evidence that Hizbullah was behind a bomb attack last July on its soil that killed five Israelis was "circumstantial" and "not categorical" at this stage.

The minister, Kristian Vigenin, said that as a result, Sofia would not back the European Union labeling the Lebanese organization’s military wing a "terrorist" entity without proof from other cases, the AFP news agency reported.

"For us it is important that this case is not based only and solely on what happened in Burgas as, in my opinion, the evidence is not categorical," Vigenin told state BNR radio Wednesday.

He said that this was the case "even if there are indirect reasons and traces that could lead to the impression that this organization is behind the attack."

"There are indications that it is possible (Hezbollah was behind the attack)."

"But we cannot take hard decisions with consequences for the politics of the European Union in the region based only on circumstantial evidence," he added, according to AFP.

The July 18 attack saw a lone bomber blow himself up near a bus of Israeli tourists at Bulgaria's Black Sea airport of Burgas, killing five Israelis, their Bulgarian bus driver and himself.

Israel has maintained that the attack, the deadliest on Israelis abroad since 2004, was perpetrated by Iran and its "terrorist" proxy Hizbullah.

It however took over six months for Bulgaria's previous conservative government to come to what it called a "justified conclusion" that two aides of the bomber belonged to the powerful Lebanese Shiite movement.

The announcement led to renewed calls for the European Union to join the United States in adding Hizbullah's military wing to its list of "terrorist" groups.

Last month the EU opened the door to such a move following a formal British request, but the decision will require unanimous approval from all members of the bloc.

"If of course the evidence from other cases is serious enough, then we would not hesitate to support such a decision," Vigenin said, according to AFP.

"At this stage the discussions will continue as well as the gathering of information and evidence."

He added however that Bulgaria would not go against such a move if there was "common consensus" among other EU nations.