WASHINGTON — President Bush, addressing the Iranian people yesterday on the eve of their presidential election, denounced Iran's electoral system as undemocratic and vowed that the United States would stand with those seeking "freedom" in the Islamic republic.

In a statement distributed by the White House, Bush said, "Today, Iran is ruled by men who suppress liberty at home and spread terror across the world. Power is in the hands of an unelected few who have retained power through an electoral process that ignores the basic requirements of democracy."

He added, "The June 17 presidential elections are sadly consistent with this oppressive record."

The statement amounted to a repudiation of the elections and the seven candidates for president, including three who have campaigned as reformists and are considered relative moderates by local standards. This group includes the front-runner, Hashemi Rafsanjani, 70, a Shiite cleric who has served two previous presidential terms. Although he was formerly known as a hard-liner, Rafsanjani now bills himself as a reformer who intends to improve relations with the West, including the United States, and liberalize the economy.

It was not clear how Bush's criticism would play in Iran, where many people, especially the young, have become alienated by 26 years of rule by fundamentalist Shiite clerics. These hard-liners hold unelected positions with supreme authority over the elected government and legislature.

It was this theocratic structure that was the main target of Bush's statement yesterday.

"Across the Middle East, hopeful change is taking place," Bush said, citing elections in Afghanistan, Iraq, Lebanon and the Palestinian territories. "People are claiming their liberty. And as a tide of freedom sweeps this region, it will also come eventually to Iran."

Bush said Iran's unelected rulers rejected more than 1,000 presidential candidates, "including popular reformers and women who have done so much for the cause of freedom and democracy in Iran."

He said Iranians "deserve a genuinely democratic system in which elections are honest — and in which their leaders answer to them instead of the other way around." He called for a free media, freedom of assembly, a "free economy" independent of the state, an independent judiciary and religious freedom.

"Today, the Iranian regime denies all these rights," Bush said. "It shuts down independent newspapers and Web sites and jails those who dare to challenge the corrupt system."

Bush concluded: "America believes in the independence and territorial integrity of Iran. America believes in the right of the Iranian people to make their own decisions and determine their own future. America believes that freedom is the birthright and deep desire of every human soul. And to the Iranian people, I say: As you stand for your own liberty, the people of America stand with you."

Although Bush did not mention any Iranian leaders by name, his statement appeared designed to drive a wedge between the public and the system headed by Ayatollah Ali Khamenei, who holds the lifetime title of supreme leader. He is the successor to Ayatollah Ruhollah Khomeini, the hard-line Shiite cleric who led a 1979 revolution against the Iranian monarchy and made the country an Islamic republic. Khomeini died in 1989, and an assembly of senior clerics chose Khamenei to fill his role.

In addition to the supreme leader, who has final say on all state matters, the theocracy vests power in a Guardian Council, an unelected body of 12 clerics and Islamic jurists that can veto any legislation it considers un-Islamic and bar any candidate from running for president or Parliament.

The current president, Mohammad Khatami, was elected in 1997 in a landslide over a hard-line candidate and was re-elected in 2001. A moderate cleric, he has sought to institute reforms but has been largely stymied by Iran's theocratic overlords. He is barred from running for a third consecutive term.

Rafsanjani, who was president from 1989 to 1997, heads the Expediency Council, a body that arbitrates between the 290-member Parliament and the Guardian Council.

Even if he comes out on top of the seven-man field (women are barred from running), Rafsanjani is considered unlikely to win a majority of the vote, a development that would force a runoff between the two top vote-getters later this month.