By Parisa Hafezi

Iran's moderate presidential candidate congratulated his hardline rival hardline judge Ebrahim Raisi for winning the election, Iranian state media reported on Saturday, as the interior ministry said counting of the votes continued.

Millions of Iranians voted on Friday in a contest that has been expected to hand the presidency to Raisi, a hardline judge who is subject to U.S. sanctions for alleged human rights abuses, including overseeing the executions of thousands of political prisoners in 1988.

"I hope your administration, under the leadership of Supreme Leader Ayatollah Ali Khamenei, will make the Islamic Republic proud, improve livelihood and ensure the nation's well-being and welfare," said former central bank chief Abdolnasser Hemmati in a letter, media said.

In a televised speech, outgoing President Hassan Rouhani congratulated "the people's elected (president)", without naming him.

"Because it has not been officially announced yet, I will delay the official congratulations. But it is clear who received the votes," Rouhani said.

The interior ministry is to announce the final results later on Saturday as the counting of the votes continued, state TV said.

Other candidates also congratulated Raisi, who was sanctioned by the United States in 2019 shortly after being appointed by Khamenei as the judiciary chief.

Hoping to boost their legitimacy, Iran's clerical rulers had urged Iranians to turn out and vote on Friday, but dissidents inside and abroad said popular anger over economic hardship and curbs on freedoms kept many Iranians at home.

Another deterrent for many pro-reform voters was a lack of choice, after a hardline election body barred heavyweight moderate and conservative candidates from standing. Opinion polls suggest turnout around 44%, lower than previous elections in the Islamic Republic.