SAN FRANCISCO -- The US Senate on Wednesday narrowly rejected a Democratic-led effort to remove US armed forces from hostilities within or against Iran that have not been authorized by Congress.

The Senate voted 50-49 against the motion, introduced by Democratic Senator Jeff Merkley of Oregon.

Three Republican senators -- Rand Paul of Kentucky, Susan Collins of Maine and Lisa Murkowski of Alaska -- voted with most Democrats to advance the measure. Democratic Senator John Fetterman of Pennsylvania voted with most Republicans against it.

The vote was the first in the Senate since the conflict the United States and Israel jointly launched against Iran on Feb 28 hit a 60-day deadline on May 1. The US administration declared then that a ceasefire had "terminated" hostilities against Iran.

The resolution states that Congress has not declared war on Iran or enacted a specific statutory authorization for the use of military force within or against Iran. It would require the president to remove US armed forces from such hostilities unless explicitly authorized by a declaration of war or a specific authorization for use of military force.

Under the War Powers Resolution, a federal law passed in 1973, the president shall terminate the use of US armed forces within 60 calendar days after a report is submitted or required to be submitted, unless Congress has declared war, enacted a specific authorization, extended the period by law, or is physically unable to meet due to an armed attack on the United States. The law allows an additional 30-day extension under certain military necessity conditions.