Unexpectedly, the Republican-led Senate passed three resolutions to prevent the sale.
The three judges at the Court of Appeal in London ruled it was "irrational and therefore unlawful" for International Trade Secretary Liam Fox to grant weapons licences without checking whether they were intended for use in Yemen or not.
Menendez, the top Democrat on the Senate Foreign Relations Committee, said the disapproval resolutions also reflected Congress' desire to preserve its powers to declare war and review major foreign weapons sales.
"We welcome this tremendous news".
The UK Court of Appeal ruled in favor of the Campaign Against Arms Trade on Thursday, finding that a 2016 shift in policy resulted in illegal sales of arms to Saudi Arabia.
The United Nations has described the conflict in Yemen, which has killed tens of thousands of people including thousands of civilians, as the world's worst humanitarian crisis.
Saudi Arabia accounts for almost half of the arms exports of the United Kingdom and a major source of revenue as so far arms sales worth $6 billion have bee carried out. In addition, it concluded that the state had "made no attempt" to assess whether Riyadh had breached global humanitarian law in the ongoing Yemen war.
Since the Saudi-led coalition began its military intervention in Yemen in 2015, the United Kingdom has licensed at least 4.6 billion pounds ($6bn) worth of arms to Saudi forces.
Alarmed by the rise of a group they saw as an Iranian proxy, the UAE, Saudi Arabia and seven other Arab states intervened in an attempt to restore the government.
Sen. Bob Menendez, D-N.J., introduced the measures, citing Saudi Arabia's role in the war in Yemen, where a Saudi-led coalition has been engaged in a multi-year campaign against Houthi rebels, often with disastrous consequences for the civilian population.
"We don't sell weapons to China because we have disagreements and we don't think it would be in our best interest to sell them weapons", said Paul, calling Saudi Arabia itself, "untrustworthy".
Britain accounts for 23% of arms imports to Saudi Arabia and previous year signed a multi-billion-pound preliminary order with Riyadh for 48 Eurofighter Typhoon fighter jets.
Mr Fox made no references to existing arms sales contracts and did not imply that all exports to Britain's traditional Middle East ally would halt.
Legally, the Court of Appeal can not make decisions on whether Britain should transfer weapons to Saudi Arabia or not.
This is not the first time that Moran has condemned actions by the Trump administration.
"We must also question a system - and the priorities of government - that have allowed the continuing provision of arms in these circumstances".