ARGENTINA’S foreign policy has grown increasingly combative in recent months. In addition to turning up the heat in its longstanding dispute with Britain over control of the Falkland Islands, the government of Cristina Fernández de Kirchner also nationalised a Spanish-controlled oil company without providing a penny of compensation and sparred with Ghana over the impoundment of a naval frigate.

This week Argentina added Israel to its list of burnt bridges. On January 27th its foreign ministry announced the country would collaborate with Iran to form a joint truth commission that will investigate the 1994 car bomb attack at AMIA, a Jewish community centre in Buenos Aires. No one has been convicted for involvement in the bombing, which killed 85 and injured 300. But Argentine prosecutors, Interpol, Israel and Jewish advocacy groups have all publicly accused Iran of directing the attack and dispatching Hizbullah to execute it.

The long investigation of the bombing has been marred by corruption, obfuscation and political intrigue. Despite the confidence of the Argentine courts, some important sources still question whether Iranian officials actually ordered the attack. James Bernazanni, a former head of the Hizbullah unit at America’s Federal Bureau of Investigation and assistant to Argentine investigators, has said that although he suspects Iran did participate in the attack, the Argentines have only offered tenuous proof.

Iran denies all involvement, and hopes the new commission will establish its innocence. If approved by the legislatures in each country, as expected, it will consist of five members that cannot be native to either Argentina or Iran—two appointed by each country—plus a president agreed upon by both. The commissioners will review all of the information gathered by each side, allow Argentine authorities to interview suspects in Tehran and eventually make suggestions in line with each country’s laws.

On January 27th Ms Fernández called the accord “historic” no fewer than 10 times on Twitter. “Historic,” she wrote, because “after almost 19 years since the AMIA bombing, we’ve achieved for the first time a legal instrument of international law between Argentina and Iran to advance knowledge of the truth about the attack.”

Israel begs to differ. Its foreign ministry summoned the Argentine ambassador to explain the decision, and released a statement saying he had been made aware of the country’s “astonishment and disappointment”. The statement also said Argentina had displayed an “unacceptable attitude” towards Israel.

Many prominent Argentine Jewish leaders agree. They argue that Iran will never allow the commission to reveal incriminating information. “How will it be possible to close the case by collaborating with those who have denied any part in the bombing?”, asks Sergio Widder, the Latin America director for the Simon Wiesenthal Center. “Furthermore, how can Argentina trust a totalitarian regime with absolutely no respect for human rights?” Both AMIA itself and DAIA, the country’s umbrella Jewish group, issued a statement criticising the agreement. The reaction abroad has also been harsh: David Harris, the executive director of the American Jewish Committee, likened the formation of the commission to “asking Nazi Germany to help establish the facts of the Kristallnacht”.

The decision could cause further tension between the Argentine government and the country’s Jewish community, which is the world’s seventh-largest and by far the biggest in Latin America. Ms Fernández’s late husband and predecessor as president, Néstor Kirchner, was viewed fondly by many Argentine Jews. He was credited with reviving the AMIA case after many years of inefficient investigation, and frequently met Jewish leaders. During his presidency the Argentine courts formally charged eight Iranian officials, including a former president of the country, for involvement in the AMIA attack.

After taking office, Ms Fernández bolstered her standing with la colectividad—as Argentine Jews often call themselves—by appointing numerous Jews to high cabinet positions. They include Axel Kiciloff, the deputy economy minister, and Héctor Timerman, the foreign minister. The selection of Mr Timerman was particularly notable because his father Jacobo was a well-known Jewish newspaper editor, who fled to Israel after being jailed and tortured during Argentina’s 1976-83 military dictatorship.

In late 2011, however, Ms Fernández poured cold water on the relationship by softening her diplomatic stance towards Iran. That year, the Argentine delegation did not walk out of the speech at the annual UN general assembly meeting given by Mahmoud Ahmadinejad, Iran’s president, as it had done for years in the past. Earlier this year, Jewish leaders were alarmed to hear reports that Argentine officials were talking to their Iranian counterparts about finding a joint solution to close the case.

Iran’s interest in the accord is easy to understand. Because of the harsh economic sanctions levied on the country over its nuclear programme, it is suffering from shortages of many essential goods, and is desperate for allies and trade partners. Argentina has not honoured the sanctions, and has become the seventh-biggest exporter to Iran, mainly supplying the country with corn, soyabeans and wheat. During Ms Fernández’s presidency, Argentine exports to Iran have soared from $319m to $1.08 billion.

Argentina’s rationale is less obvious. According to Sergio Berenzstein, a political consultant, Ms Fernández may be cozying up to Iran as a gesture of support to its leftist allies in Latin America, such as Cuba and Venezuela, as well as seeking to promote a “multi-polar world” not dominated by the traditional Western powers. But she could have economic reasons for improving ties to Iran as well. Argentina’s interventionist policies have forced it to import ever-greater amounts of energy. And Iran is likely to offer generous terms to any country willing to thumb its nose at the West and buy Iranian oil.

This post was updated on January 30th.