World powers cautiously welcome new Iran leader

World powers offered cautious welcome Saturday to moderate cleric Hassan Rowhani after he was declared Iran's new president, amid persistent concerns over Tehran's nuclear program.

The 64-year-old's election ends eight years of conservative grip on the top office in conservative Iran, and he used his first statement after the win was confirmed to announce a "new opportunity" for the West to treat the Islamic republic with respect and to recognize its rights.

The United States said it was prepared to engage Iran directly over its disputed nuclear program.

The White House said such engagement would be aimed at reaching a "diplomatic solution that will fully address the international community's concerns about Iran's nuclear program."

It criticized lack of transparency, censorship of the media, the Internet and text messages during the vote, along with an "intimidating security environment that limited freedom of expression and assembly."

The West suspects the program is aimed at building nuclear weapons, but Iran insists it is for peaceful purposes like generating energy.

Rowhani has previously vowed to restore diplomatic ties with the US, which cut relations in the aftermath of the 1979 seizure of the US embassy by Islamist students.

UN Secretary-General Ban Ki-moon urged Iran to play a "constructive role" in regional and international affairs, his office said in a message congratulating Rowhani and welcoming the reported high turnout.

Ban "intends to remain engaged with the Iranian authorities and with the president-elect on issues of importance to the international community and the welfare of the Iranian people," his office said in a message congratulating Rowhani.

EU foreign policy chief Catherine Ashton said she was committed to working with Rowhani to find a "swift diplomatic solution" on finding a solution to the disputed nuclear programme.

Ashton serves as chief negotiator for the six world powers seeking to check Iran's controversial nuclear ambitions.

French Foreign Minister Laurent Fabius said Paris was "ready to work" with Rowhani, and said the country's nuclear programme and its involvement in the Syrian conflict would be high on the agenda.

Britain urged Rowhani to set the Islamic republic "on a different course," while German Foreign Minister Guido Westerwelle welcomed Rowhani's election as a vote for reforms and "a constructive foreign policy."

"We hope that the country's new administration collaborates in this sense in order to reach solutions on international and regional questions," Westerwelle said.

Italian Foreign Minister Emma Bonino said Italy hoped to launch a "relationship of renewed comprehension and constructive dialogue" with Iran after the election of its new president.

But Israel said it was supreme leader Ayatollah Ali Khamenei who determines nuclear policy, not the president.

"After the election, Iran will continue to be judged by its acts, in the nuclear field as well as that of terrorism," a foreign ministry statement said.

The Jewish state, the region's sole if undeclared nuclear power, has not ruled out a military strike to prevent Iran developing an atomic bomb.

The key opposition Syrian National Coalition called on Rowhani to review support for Syria's President Bashar al-Assad.

At home, the supreme leader hailed Rowhani on his victory.

"Congratulations to the people and to president-elect Hojatoleslam Hassan Rowhani," Khamenei's website reported.

"I urge everyone to help the president-elect and his colleagues in the government, as he is the president of the whole nation."