Prime Minister Masayoshi Ohira appealed today for the release of the 50 American hostages held at the U.S. Embassy in Tehran and said his government would cooperate with the Europeans to avert a bigger crisis between Iran and the United States.

But Ohira's speech to foreign reporters offered no new insight into what Japan would do in support of American economic and diplomatic sanctions against Iran.

Another Pacific ally, Australia, stepped up its attacks on Iran today. Foreign Minister Andrew Peacock declared that Australia is unashamedly supporting the United States as a friend and ally."

The United States is urging its allies to cut diplomatic relations and impose economic sanctions against Iran until the hostages are freed. So far, Japan has kept its intentions carefully hidden. It went along with European allies in asking for a timetable of the hostages' release and then called its ambassador home for a report, emphasizing that it was not breaking relations.

Ohira said today he hopes to maintain "correct relations" with Iran and in a vague offer of future help said Japan hopes to "cooperate with nation-building in the new Iran."

"I therefore appeal most strongly to the leaders and people of Iran that the hostages at the U.S. Embassy be released at the earliest possible opportunity," he said.

Ohira acknowledged that Japan frequently has been vague in disclosing its plans in the hostage crisis and appealed for understanding of the "constraints" it operates under, a veiled reference to its need for Iranian oil.

Earlier this week Australia announced it would not replace its retiring ambassador in Tehran until the crisis is solved, and it closed its trade commissioner office there.