WASHINGTON -- The U.S. Senate voted unanimously Friday to impose new sanctions on Iran's domestic industries, targeting the Islamic Republic's economy in an effort to thwart its nuclear ambitions. The Obama administration had objected, saying the sanctions could undermine current ones.

The 94-0 vote reflected fears about a possible nuclear weapons program and the strong desire to protect the United States' closest Mideast ally, Israel. Shortly before the vote, the powerful American Israel Public Affairs Committee urged senators to back the measure.

The measures build on sanctions on Tehran's oil and financial industries that Congress approved in the past year.

"The screws need to be tightened," said Sen. John McCain.

Iran maintains that its nuclear program is for peaceful purposes only.

The new sanctions would designate Iran's energy, port, shipping and ship-building sectors as entities of proliferation and sanction transactions with these areas. The legislation also would penalize individuals selling or supplying commodities such as graphite, aluminum and steel to Iran, all products that are crucial to Tehran's ship-building and nuclear operations.

The legislation also would designate the Islamic Republic of Iran Broadcasting and its president as human rights abusers for broadcasting forced televised confessions and show trials.

In a memo from the National Security Council just hours before the vote, the Obama administration argued that the new sanctions were unnecessary, duplicative and "threaten to confuse and undermine" provisions in current law.

Specifically, the administration complained about the omission of waivers that would give the president more flexibility, ambiguities that would make implementation difficult and requirements for congressional reports on thousands of small and mid-size vessels that dock at Iranian seaports that were too burdensome.

The Associated Press obtained a copy of the memo.

The United States and European Union have imposed tough sanctions on Iran that have weakened its economy, but Tehran has found ways to bypass the penalties, such as Turkey's use of gold to pay for Iranian natural gas imports.

The president has 90 days from the legislation's enactment to act. The bill does include the authority to waive the sanctions based on national security.

The Senate also has revived a divisive debate over civil liberties and the president's powers as commander in chief, voting that American citizens suspected of terrorism and seized on U.S. soil may not be held indefinitely.

Ignoring a White House veto threat, a coalition of liberal Democrats and libertarian Republicans late Thursday backed an amendment to a sweeping defence bill that said the government cannot detain a U.S. citizen or legal resident indefinitely without charge or trial, even with the authorization to use military force or a declaration of war.

The strong bipartisan approval sets up a fight with the House of Representatives, which rejected efforts to bar indefinite detention when it passed its bill in May.

Current law denies suspected terrorists, including U.S. citizens seized within the nation's borders, the right to trial and subjects them to the possibility they would be held indefinitely. It reaffirms the post-Sept. 11 authorization for the use of military force that allows indefinite detention of enemy combatants.

That generated a conservative backlash as well as outrage among civil liberties groups.

In arguing for her amendment, Sen. Dianne Feinstein recalled the dark days of World War II when the United States forcibly removed thousands of Japanese-Americans and placed them in permanent internment camps amid unfounded fears that they were spies and national security threats.

Lawmakers also approved an amendment that would prevent the transfer of detainees held at Guantanamo Bay, Cuba, to prisons in the United States.

Sen. Kelly Ayotte argued that the 166 terror suspects, including Khalid Sheikh Mohammed, the self-styled mastermind of the Sept. 11, 2001, attacks, should remain at the U.S. naval facility and not be transferred to any facility on American soil.

The administration, in threatening to veto the bill, strongly objected to a provision restricting the president's authority to transfer terror suspects from Guantanamo to foreign countries. The provision is in current law.

The $631 billion defence policy bill for next year authorizes money for weapons, ships, aircraft and a 1.7 per cent pay raise for military personnel. The total is $4 billion less than the House-passed bill, and House-Senate negotiators will have to work out the difference in the closing days of this year.