U.S. government officials have yet to begin working out understandings with banks and corporations holding legal claims against the $8 billion in frozen Iranian assets that would pave the way for an early release of that money to Iran, informed sources said yesterday.

"The freeing of all our assets" was one of the conditions for the hostage release announced last month by Ayatollah Ruhollah Khomeini. But administration officials said yesterday that until they could see exactly what conditions were set by Iran's parliament, they were unable to determine what steps might be needed to free those assets.

At the State Department yesterday, spokesman John Trattner said there have been "no communications from Iran of which I'm aware . . . we're in a posture of watching and waiting."

Other government officials suggested that Iranian government officials who wanted quickly to push through the parliament conditions for the hostages' release along the general lines of Khomeini's statement had run into stronger than expected opposition from a militant, anti-American minority. That view was echoed in telephone conversations with Iranian officials in Tehran.

One illustration of the problem for Washington is seen in another of Khomeini's conditions, that the United States should return the wealth of the late shah Mohammad Reza Pahlavi.

Although there was no official response, government officials said privately that the United States would be willing to assist the Tehran government in any court action in this country directed at getting control over any money or property that belonged to the late shah. As one official said yesterday, "That one is simple. The courts are open and we have no control over the shah's estate, nor do we know what it consists of."

Interviews with Iranian officials both in New York and, by telephone, in Tehran, show there may not yet a be single view on what the Khomeini condition, itself, really is. In fact, no one is certain whether reference to the shah's wealth includes that of his entire family or just what left Iran in his name.

The Iranian ambassador to the United Nations, Ali Shams Arkakhani, said yesterday in a television interview that "what's important" in dealing with the condition about the shah's wealth "is that the U.S. would agree or make a pledge that upon finding the shah's money which had been inappropriately taken by him, the United States would not hinder anything returning."

In Tehran, another Iranian official who once said such a pledge would be satisfactory, now says more would be needed to satisfy the parliamentary hardliners. He suggested that President Carter might have to issue a declaration that "money that left Iran under the control of the shah now belongs to the Iranian government."

A Washington official who has been privy to discussions on the hostage situation said yesterday that "it's still an open question" as to what will be needed to satisfy the condition on return of the shah's wealth. He added that "those who really know on the Iranian side are not talking."

The condition on returning the shah's wealth is simple compared to attempting to meet the condition of making available to the Iranians some if not all of the now-frozen $8 billion. Here again, sources said yesterday, it is still unclear what the Iranians will finally end up asking for.

The head of the Iranian central bank, Ali Reza Nobari, in a telephone interview from Tehran last Saturday, said that a "guarantee" from the United States, either directly or through a third-party that some of the funds would immediately become available would meet that condition, at least in part. Thereafter, Nobari said, specific neogtiations would be needed to work out the legal claims that have been filed against the money by U.S. banks and corporations that say the Iranian government owes them money.

Although the question of returning the Iranian assets has been before the U.S. government for months, federal officials and a handful of the bank and corporate claimants contacted yesterday said there have been no plans worked out on how the problem would be handled.

Many banks have used Iranian deposits to cover Iranian loans that were declared in default. Reinstating those funds to the Khomeini regime would be a difficult operation, banking sources said. "It would not be impossible to do," the source added.

Corporate claims vary. They range from oil drilling companies which have sued for payment on multimillion-dollar drilling rigs that were seized by the Khomeini regime, to companies like du Pont that invested more than $40 million in a fiber plant that was nationalized, to computer companies whose million-dollar service contracts were summarily broken.

"These companies have covered their cash losses" by getting court orders against the frozen assets, one banker said yesterday, "and they are not about to give away that covered position."

A government official yesterday said it could take months to work out the assets condition, "depending on the detail we get into."

On the other hand, sources close to the Iranian officials who want to work the problem out quickly said one posibility is that a general guarantee would be arranged and the Iranian prime minister or foreign minister given authority by the parliament to work out the obviously complicated details.

Washington sources, who would like to see the hostage release take place sooner rather than later, are hoping the Iranian parliament sticks to the generalized conditions laid out by Khomeini last month, instead of attempting to get too specific on details that would only complicate matters.