WASHINGTON — US Sen. Chris Murphy, D-Conn., said he is is proposing a bill to limit US munition sales to Saudi Arabia in protest for its conduct of the war in Yemen. 

Murphy, a member of the Senate Foreign Relations Committee, said he is troubled by civilian deaths in the Saudi-led bombing campaign and would like to see restrictions placed on US sales of air-to-ground bombs. Though he said support for the measure might be slim, he sees "a growing discomfort [in Congress] about the growing level of arms sales to the Mideast, and a lot more people willing to ask questions than there were just a few years ago."

The legislation, which would be focused on future sales of air-to-ground munitions to Saudi Arabia, is co-sponsored by Sen. Rand Paul, R-Ky.

The comments come as a United Nations-brokered cease-fire went into effect in Yemen on Sunday. Forces loyal to the Yemeni government, backed by Saudi Arabia, and the Shiite rebel Houthi militia agreed to a truce ahead of a planned resumption of peace talks in Kuwait, CNN reported. The United Nations estimates 9,000 casualties, including more than 3,000 civilian deaths in the Yemeni conflict from March 2015 to 2016.

"I'm increasingly worried the Saudi-led bombing campaign in Yemen is not supporting US national security interests," Murphy said. "I've been hearing regularly, in Yemen, that this is being seen as a US campaign. It's clearly creating more, not less, space for extremist groups to operate, and I think the bar should be higher for the US to send replacement munitions."

The US in November cleared a sale of more than 10,000 advanced air-to-ground munitions for Saudi Arabia, a week after key allies in the Gulf Cooperation Council raised concerns over dwindling supplies of weapons. The value of the sale — which includes tens of thousands of laser-guided bombs — is $1.29 billion, with a supplier to be determined by competitive bid.

Saudi Arabia-led coalition airstrikes using US-supplied bombs killed at least 97 civilians, including 25 children, in northwestern Yemen on March 15, Human Rights Watch said last week. The organization reported finding the remnants at the market of a GBU-31 satellite-guided bomb, which consists of a US-supplied MK-84 2,000-pound bomb mated with a JDAM satellite guidance kit, also US-supplied; ITV, a British news channel, reported finding remnants of an MK-84 bomb paired with a Paveway laser guidance kit.

The arms sales to Saudi Arabia raise broader concerns about rising US sales to the region as it seeks to beef up the ability of allies to fight against the Islamic State group, Murphy said. While enlisting Gulf states into the fight against ISIS is a key goal of the administration's foreign policy, countries in the region have also sought US weapons in the wake of the US nuclear agreement with their historic foe, Iran.

"There's been a dramatic increase in arms sales to the region in the wake of the Iran agreement, but Yemen is an example where our partners have used US arms irresponsibly resulting in the deaths of thousands of civilians. I do think Congress needs to get back in the game," Murphy said.

The legislation would subject any future air-to-ground munitions transfers to Saudi Arabia to a certification by the president that the government of Saudi Arabia is not providing funding, materiel support or lethal aid to any designated foreign terrorist organization, and that it take "all necessary measures" to target such organizations, including al-Qaida in the Arabian Peninsula and affiliates of ISIS, as part of its military operations in Yemen.

The government of Saudi Arabia must also take "all feasible precautions to reduce the risk of harm to civilians and civilian infrastructure," in compliance with international humanitarian law and the US Arms Export Control Act, and the country must facilitate humanitarian aid distribution.

It will be an uphill fight to get colleagues to support the measure, which had yet to be introduced Tuesday afternoon. The goal, he said, is to spark a discussion in Congress about the civil war in Yemen and the broader issue of arms sales to the Middle East.

"I think there is almost no discussion here in Congress about the dramatic uptick in arms sales to the Mideast over the last four years and the potentially deleterious effect of the Yemen civil war on US national security interests," Murphy said.

Murphy drew a parallel between his proposal and a failed proposal from Sen. Rand Paul, R-Ky., to block US funding for the sale of fighter jets to Pakistan. Paul's proposal was defeated 71-24, though Murphy read the 24 votes as positive.

"I don't think it's out of the realm of possibility that we could grow support for this resolution but its going to take time and education," Murphy said.

Senate Armed Services Chairman John McCain, R-Ariz., said he strongly disagrees with Murphy, suggesting that lethal aid from the United States to Saudi Arabia has been a vital check on Iran's expanding influence.

"The Iranian backed Houthis were about to take over Yemen, so I suggest he reevaluate," McCain said of Murphy. "We wouldn't do anything about it, so the Saudis did."

Twitter: @reporterjoe