PARIS, AUG. 8 -- As revolutionary Iran shouts defiance in the Persian Gulf, the heir of the late shah of Iran has decided to end his relative obscurity in exile in the United States and seek international recognition as a leader of the opposition to the radical Islamic government in Tehran.

Reza Pahlavi II, 26, who proclaimed himself shah soon after his father's death in Cairo in 1980, inaugurated his new visibility with a round of interviews and television appearances this week in Paris. The time has come, he said, to show himself as the focal point for a broad movement to replace Ayatollah Ruhollah Khomeini with a constitutional monarch on his father's Peacock Throne.

"The people need to know me on the propaganda level," he said. "I have to make more speeches into Iran. They need to know through me that things also are going on outside."

Exile groups opposed to Khomeini's rule range from the leftist Mujaheddin-e-Khalq, an underground organization that receives support from Iraq and is based in Baghdad, to monarchist groups that look toward the royal heir for leadership and, according to exile sources, have received CIA financing and other aid.

Former president Abol Hassan Bani-Sadr, who lives in a Paris suburb, said neither current enjoys support among the people of Iran, because the Mujaheddin is identified with Iraq, Iran's enemy in war, and the monarchists are identified with the United States and the deposed shah.

"How do you expect an agent of the CIA to become king of Iran?" he said when asked about Pahlavi's chances of gathering popular support. "The people know you cannot restore life to a monarchy that was overthrown by a big revolution."

The young Pahlavi's decision to play a visible leadership role in monarchist opposition groups was a reversal; previously, one of his followers said, he was reluctant to be closely identified with such activities among the many conservative Iranian exiles in Europe and the United States.

Pahlavi said in an interview that he has worked quietly in the past eight years to build a clandestine network of contacts and supporters, including military officers and government officials, within Iran. Now, he said, he will seek to unite the often squabbling monarchist opposition groups under his banner and make their activities better known on the world stage and within Iran.

"The reason they failed is not that they didn't do anything," he said. "The reason is that they didn't see they had to do it in unison. Because they failed in this, I have to step in today and accept this extra responsibility."

Monarchist exiles have gravitated chiefly to movements headed by former prime minister Shahpour Bakhtiar and former education minister Manuchehr Ganji in Paris and ailing former prime minister Ali Amini in London. None of the movements has been active enough within Iran to generate wide notice abroad, however, and there was no way to assess their prospects for support with the young exile king as an active symbol.

The Paris-based groups had been forced to keep a low profile during Prime Minister Jacques Chirac's year-long effort to normalize French-Iranian relations. With the two countries in an angry confrontation since June, these restrictions appear to have been relaxed.

In that light, some sources suggested, Pahlavi might take up residence here. Asked about this, he said he plans to move frequently between the United States and Europe and -- provided the governments involved will let him -- would like to get closer to Iran by setting up a headquarters in a border country such as Turkey or Pakistan.

Pahlavi and his aides said a broad section of the Iranian people supports the idea of his return to the throne. It has become more urgent to work in that direction recently, a follower added, because Khomeini is ill and his death is likely to increase chances for swift change as competing religious leaders vie for power.

The shah-in-exile, whose aides address him as "majesty" and bow when they approach him, said he would like to be monarch under the 1916 Iranian constitution. His rule would be similar to that of Spain's king, he added, with parliamentary democracy operating freely under a royal chief of state.

"I will respect wholeheartedly the expression of popular sovereignty," he said.