Refusal by the United States to accept World Court jurisdiction over a suit condemning U.S. actions in Nicaragua would be "identical to the position of the Ayatollah Khomeini" in refusing to release the American hostages in Iran four years ago, an attorney for the Nicaraguan government said yesterday.

Paul Reichler, who represents Nicaragua before the International Court of Justice in The Hague, also called the World Court, joined Nicaragua's new ambassador to the United States, Carlos Tunnermann Bernheim, at a news conference.

They expressed "hope" that the United States will accept the court's decision Monday that it does have jurisdiction over Nicaragua's suit demanding an end to U.S. support for "military and paramilitary activities" against Nicaragua's leftist Sandinista government.

Nicaragua also is demanding $250 million in compensation for war damages allegedly inflicted by U.S.-backed rebel forces.

Reichler said U.S. refusal to accept World Court jurisdiction would be a major break with U.S. tradition of backing the court's decisions, including its 1980 order that Ayatollah Ruhollah Khomeini release the hostages and return the U.S. Embassy in Tehran to American control.

"It would be ironic . . . and sad" for the Reagan administration to be "following in the footsteps of the Ayatollah Khomeini," Reichler said. He said the U.S. stand would be "identical" to Khomeini's.

Asked if he endorsed that view, Tunnermann said Reichler was speaking as an individual. "I make no comparisons with any other government," he said.

The United States argued that the case should come under the jurisdiction of the U.N. Security Council, not the World Court, in part because Nicaragua had never deposited formal documents of ratification of court jurisdiction.

The court rejected that view, and Tunnermann said yesterday that Nicaragua had demonstrated its adherence to the court in 1960 by turning over 18,000 square kilometers of territory to Honduras after a World Court ruling on their border dispute.