A CIA report released in 2010, yet not reported on until now, suggests there was a budding relationship between Iran and Yasser Arafat's Fatah party in the Islamic Republic's early days, referring to the Palestine Liberation Organization (PLO) as "one of Iran's closest allies" in 1980 and Ayatollah Khomeni as one of Arafat's earliest backers. Fearing a significant Palestinian role in Iran's internal affairs, however, the regime worked to limit the PLO's presence in the country. The report confirms a February 19, 1979 story in The Washington Post that claimed Arafat was the first foreign leader to visit Tehran after the Islamic Revolution in 1979. Citing Iranian media reports, the story reported that Iran broke diplomatic relations with Israel just hours after Arafat met with Iran's new cabinet. "An obviously overjoyed Yasser Arafat wound up two days of meetings with leaders of Iran's revolution here today and said the overthrow of the [pro-West] shah by a militantly Moslem movement offered a 'new dawn and a new era' to the Middle East struggle," the Post wrote.According to the CIA report, the PLO's military presence in post-revolution Iran was reflective of the organization's overall role in the country: It began strong and eventually tapered off as Arafat began to embrace Iraq's Saddam Hussein, who had hostile relations with Iran.Regime-opponent Shapour Bakhtiar, who served as Iran's last prime minister before the revolution, is quoted in the document as claiming there were over 20,000 Palestinian advisors in Iran under Khomeni as of 1980, and other government critics are mentioned as charging that Palestinians piloted Iranian aircraft and were present among the militants holding the US embassy in November 1979.Shortly after the revolution, a PLO mission was dispatched to Tehran to help train Iran's Revolutionary Guards Corps at Khomeni's invitation, but played little role as Iranian officials were weary of a heavy Palestinian influence on the Iranian military.Only about half a dozen PLO military officials remained in Tehran attached to the Guards as of August of 1980, according to the report.The PLO's main presence was in Tehran. "Immediately after the revolution," Khomeni gave the PLO a Tehran office building that formerly housed Israel's diplomatic mission in Iran, the report claims. The office was accorded the status of an embassy and included a military attache, press offices for the Palestine News Agency (WAFA) and a few intelligence officers. The regime also granted the PLO small offices in several other cities, including Mashhad, Shiraz, Ahvaz and Esfehan. The PLO presence in Iran was "dominated by Arafat's Fatah group which has sought to prevent other Palestinian organizations from gaining a position in the country," according to the document.While Iran has maintained a relationship with the PLO since 1979, the Shi'ite regime is also seen as a major backer of Fatah's arch-nemesis Hamas, who ousted Fatah from Gaza in 2007. The two groups engaged in reconciliation talks in late 2017.