Stood up and jilted by the Ayatollah Khomeini, public TV's Robert MacNeil stormed out of Tehran yesterday as correspondents from the three commercial networks stood in line like petitioners to Caesar in the hope the Iranian leader will talk to them.

Iranian terriorists continued to occupy the American Embassy and hold Americans hostage while network news departments jockeyed for crumbs from Khomeini's representatives. As of late yesterday, no one knew for sure if there would be separate interviews with each network, a group interview with all three networks, or no interviews with no networks.

"I don't think it's a very stable situation," ventured a spokesman for ABC News. "We have our bid in and we're hoping."

"It's not official, but there is an interview Sunday," said a spokesman for NBC News. "it's all in the planning stage, because who knows what's going to happen?"

But at CBS News, a spokesman said it was assumed that heavy-hitter Mike Wallace, now on hold in Tehran, would get his own private whack at the ayatollah today and that parts of the interview may make it to tonight's CBS Evening News, with the full interview to air Sunday night on "60 Minutes," TV's number one show in national ratings last week.

It is believed, especially by those in public TV, that the ayatollah is playing media games and is holding out for the largest possible audiences.

MacNeil, who cohosts public TV's "MacNeil/Lehrer Report," had been promised an exclusive interview with Khomeini on Wednesday. He left immediately for Tehran, only to be told on arrival that he could not see the ayatollah until Sunday, after he had spoken with newsmen from the major networks.

Al Vecchione, producer of "MacNeil/Lehrer," declined to say he was angry about the switcheroo yesterday, but did say. "We're all kind of down about it. We spent a lot of time reporting that story in the last 15 months, and we're badly disappointed.

"It's not just a question of losing a scoop. There's the potential for a historic moment here. So of course you feel depressed when it goes down the tubes."

A statement issued by "MacNeil/Lehrer" did not accuse Khomeini of violating his agreement but said that the "journalistic need . . . would be filled by the other interviews" so that MacNeil's would be unnecessary.

ABC News had Peter Jennings standing by in Tehran, and NBC News has John Hart ready to roll should the ayatollah lift his litte pinkie and agree to be interviewed. NBC expects to use the bulk of the interview, if any, on "Prime Time Sunday," Sunday night at 10.

CBS News sounds the most confident of getting an interview. "Let's put it this way: we do not act like 'macNeil/Lehrer' and say we have something when we don't have it yet," the spokesman said. "But we are supposed to have Khomeini on Saturday.

"We don't know what the ground rules are, or how long we'll have, or anything, but to the best of our knowledge, it's still Saturday.