Internal Revenue Service officials have decided to sell two luxury cars seized from South Korean businessman Tongsun Park in 1977, even though Park is still contesting the government's claim to the cars.

The IRS, which claimed Park owed the government $5 million in back taxes, in 1977 picked up a 1976 blue Cadillac E1 Dorado and a silver-gray 1976 Mercedes 450-SEL sedan from a company owned by Park.

Now the government has grown weary of paying storage charges on the cars and wishes to unload them before they depreciate, IRS officials said yesterday.

Meanwhile, Park is still contesting the government's $5 million in tax claims against him that led to the loss of his cars and other properties controlled by his corporation, Pacific Development Inc. Court hearings on a suit filed by Park against the IRS are scheduled to begin in April.

"That's the power of the IRS for you," said William Hundley, one of Park's lawyers. "Once the IRS district director, in his great wisdom, decides to attach your property, it's all downhill from there. You might as well forget it."

The IRS says that its actions are completely proper, however. "Where it can be ascertained that attached property is a depreciating asset," explained Harvey Hammer of the Baltimore IRS office, which is conducting the sale, "we may sell without the taxpayer's permission even though the liability is being litigated in tax court."

"It's hopeless," said Hundley. "They've got a regulation for everything. Park might try to buy those cars back, but they've got all his dollars tied up already. They'd have to accept Korean yen."

The IRS is accepting sealed offers for one or both of the cars from all interested persons wishing to fill out IRS form 2222, a spokesman said. The bids will be opened at the Baltimore IRS branch in Washington on March 7.