A senior Palestinian guerrilla leader says that Abu Nidal, the Palestinian accused of having organized the Rome and Vienna airport massacres, receives various types of support from conservative Arab countries as well as radical movements and that he spends time in Iran.
''Any state that finds it in its interest will support him,'' said the Palestinian leader, Ahmed Jabril, head of the Popular Front for the Liberation of Palestine-General Command, in an interview in his Damascus headquarters. Mr. Jabril's group is backed by Syria and Libya.
Mr. Jabril said Abu Nidal, whose real name is Sabry al-Banna, ''doesn't need a lot of money for his activities'' because he runs a tight organization that has limited operations.
Mr. Jabril's remarks linking Abu Nidal and Iran were made when he was asked what sort of support Abu Nidal receives from Libya and Syria, and where he gets his logistical support, such as safe haven, passports and a place from which to operate.
Mr. Jabril replied: ''Surely, Abu Nidal doesn't usually spend much time in Libya and Syria. Rather, he spends most of his time in Teheran.'' He refused to elaborate, beyond confirming that he intended to say that the Iranian regime led by Ayatollah Ruhollah Khomeini gives him support.
Rather, diplomatic and other Palestinian sources say, Abu Nidal probably gets varying degrees of financial and logistical support from several countries, including Libya and Syria, as well as ''protection money'' from conservative Arab nations.
Mr. Jabril said Abu Nidal, whom he said he saw less than two months ago, was responsible for the airport attacks in Rome and Vienna. The United States has also said Abu Nidal was behind the attacks.
Mr. Jabril's group is part of the National Salvation Front, a Syrian-based umbrella organization composed of six Palestinian groups that oppose Yasir Arafat, chairman of the Palestine Liberation Organization, and all actions other than armed struggle to win Palestinian rights.
It is impossible to determine with any accuracy how much support Syria may be giving the Abu Nidal faction. Often, the lines between the radical Palestinian breakaway factions that operate from here, and between their ideologies, are blurred.
The Abu Nidal group, for example, apparently has a skeleton operation that works out of two Damascus offices, according to diplomatic and Palestinian sources. But people who are said to be representatives of the group tell visitors that they have no authority to speak for it.
Communications of the Fatah Revolutionary Council, the official name of Abu Nidal's faction, and its weekly magazine, The Revolution of Palestine, are distributed quietly, not sold openly on the street.
The cover of the most recent issue depicted President Reagan trying to pull himself up on a chinning bar, against a background showing the wreckage of the United States Marine garrison in Beirut, which was destroyed by a suicide bomber in October 1983.