Argentina and Iran have reached a breakthrough in the investigation of a Jewish centre bombing that killed 85 people in Buenos Aires 19 years ago, agreeing to establish an independent international "truth commission" led by a jurist "with high moral standing and legal prestige" to examine Argentina's worst terrorist attack.
The commissioners will examine the evidence and recommend how to proceed "based on the laws and regulations of both countries".
Then, commissioners and Argentine investigators will travel to Tehran to question the suspects.
Cristina Fernandez Kirchner, Argentina's President, described the agreement signed on Sunday in Africa by foreign ministers Hector Timerman and Ali Akbar Salehi as "historic".
A van loaded with fertiliser and fuel oil was exploded on July 18, 1994, levelling the Argentine Israelite Mutual Association (AMIA) building.
As with a separate attack that destroyed Israel's embassy in Buenos Aires two years earlier, killing 29, the case has never been solved.
Argentinian prosecutors have formally accused six Iranians of coordinating the AMIA attack under orders from their government. Among them is Iran's current defence minister, Ahmad Vahidi.
Investigators have spent years seeking to interrogate the suspects with the help of Interpol, but Iran's government has refused until now to make them available.
'Failures and scandal'
Previous Argentinian probes resulted "only in failures and scandal, with a trial that ended up being a farce" after high-level officials were accused of covering up evidence and deliberately misdirecting investigators, Fernandez said in a series of posts on the Twitter micro-blogging service.
In contrast, this process, which needs legislative approval in both nations, provides a legal framework with due-process rights for the accused that could be a model for conflict resolution, Fernandez said, and it puts the dispute firmly in the hands of legal experts overseen by independent arbitrators.
In a tweet, she said the deal was important because the AMIA "tragedy can no longer be used as a chess piece in a game of faraway geopolitical interests".
Jewish groups, however, made clear their discomfort at Argentina's efforts to improve relations with Iran despite the unresolved bombing case.
"It is a monumental step backward," Luis Czyzewski, who lost his daughter Paola in the bombing, told Argentina's Jewish News Agency on Sunday.
"I think all the families will reject it and be as angry as I am."
A description of the agreement by Iran's FARS news agency said years of Argentine investigations "have failed to advance the case or prove anything against Iran, indicating that Iran is innocent".
Iranian President Mahmoud Ahmadinejad said in October that once "investigations take place in an accurate and impartial manner, then the ground will be prepared for the expansion of ties between Iran and Argentina", the FARS report said.