BEIRUT – The billionaire businessman chosen by Hezbollah and its allies as Lebanon’s prime minister called for a unity government Tuesday, a sign that the Iranian-backed militant group does not want to push its power too far and risk isolation abroad and an escalation of sectarian tensions at home.

In Washington, Secretary of State Hillary Rodham Clinton warned that formation of a government dominated by Hezbollah would mean changes in U.S. relations with Lebanon. The militant group and its allies ousted the government that was backed by Washington two weeks ago when they walked out of the Cabinet.

The United States deems Hezbollah a terrorist organization and has imposed sanctions against the group and its members.

The ascendancy of Hezbollah is a setback to the United States, which has provided Lebanon with $720 million in military aid since 2006 and has tried in vain to move the country firmly into a Western sphere and end the influence of Iran and Syria.

Hezbollah’s opponents maintain that having an Iranian proxy in control of Lebanon’s government would be disastrous and lead to international isolation. The militant group has its own arsenal and is the country’s most powerful military force.

Seeking to calm sectarian tensions, Prime Minister-designate Najib Mikati called for a unity government.

“My hand is extended to all Lebanese, Muslims and Christians, in order to build and not to destroy,” said Mikati, whose moderate credentials and Harvard education seem to rebut those who call a pro-Hezbollah figure with a militant agenda.

A telecoms tycoon and former prime minister, Mikati, a 55-year-old Sunni, is seen as a neutral figure in Lebanese politics. He is a friend of Syrian President Bashar Assad and also enjoys close ties with U.S. ally Saudi Arabia.

In an interview Tuesday night on local television, Mikati said he is committed to democracy and dialogue. He also rejected the notion that the government will be an Iranian proxy.

“I am not in a confrontation with the West,” he told the private LBC station. “We are looking to build good relations with the West.”

Hezbollah leader Sheik Hassan Nasrallah echoed those sentiments.

“We do not seek power and we do not seek to govern. Our minds and hearts are somewhere else,” Nasrallah said Tuesday in a televised speech. “While you go to sleep, we go to train (against Israel).”