Houthi rebels, supported by Iran, have been under attack by Saudi Arabian forces in Yemen and observers, including the UN, have claimed hundreds of civilians have been killed in aerial bombing of hospitals and schools and the bombing of a wedding in 2015, which killed 140 people.
The Houthis are Shias who are loyal to ousted president Ali Abdullah Saleh, and the conflict is seen as being part of the regional power struggle between Shia Iran and Saudi Arabia, a nation which espouses an extreme form of Sunni Islam known as Wahhabism.
Earlier in July, a report by the Henry Jackson Society found Saudi Arabia was funding Islamic extremist preachers in Britain.
British Prime Minister Theresa May is understood to have a report on her desk from her own government which also points the finger at Riyadh for stirring up extremists in Britain.
But she has maintained that commercial deals between Britain and Saudi Arabia are vitally important, including arms sales.
Since the bombing of Yemen by a Saudi-led coalition began in March 2015, Britain has licensed £3.3 billion (US$4.25 billion) worth of arms to the Saudi regime, including Tornado and Typhoon jets and £1.1 billion (US$1.42 billion) worth of missiles and bombs.
But the High Court ruled on Monday (July 10) in favor of Mrs. May and her government.
Lord Justice Burnett and Mr. Justice Haddon-Cave said CAAT had failed to prove there was "a clear risk" that the arms would be used in a "serious violation of international humanitarian law."
"The open and closed evidence demonstrates that the Secretary of State was rationally entitled to conclude… the coalition were not deliberately targeting civilians,… Saudi processes and procedures have been put in place to secure respect for the principles of International Humanitarian Law… the coalition was investigating incidents of controversy, including those involving civilians casualties," said the court in its judgement.
Some of the court's hearing was in secret and the full reasons for the judgment were not given for national security reasons.
Saeed al-Shehabi, a London-based Bahraini political activist, said he was disappointed Britain would have returned to an ethical foreign policy.
Last 2 years seen Saudis accused of turning a busy marketplace, refugee camp and multiple schools and hospitals into sites of massacres https://t.co/ItOnREudFa— CAAT (@CAATuk) July 10, 2017
"With the weakness of the elections for Theresa May, one would have expected that the Conservatives in the UK would have realized there is a change in the mood of the British public, and would relent to the request by human rights activists to suspend or reduce the extent of its involvement with the Saudis in their crimes in the Yemen, but today's judgment in the High Court has set everything back," Mr. al-Shehabi told Sputnik.
Anti-war campaigner Sam Walton said he was also "deeply dissatisfied" with the judgment.
"It's an incredibly weak judgment. When you look at what the judgment says, it basically says, 'Hey look, the Saudis say they're not bombing civilians and we believe them.' It lacks any legal rigor," Mr. Walton told Sputnik.
"In a way I am perversely satisfied because all that has happened today is that the government, through their underhand secrecy, and this very bizarre judgement, have put the issue of arms to Saudi on an even higher stage, because it's moved from the High Court to the Court of Appeal," Mr. Walton added.
The judges ruled that Foreign Secretary Boris Johnson was "rationally entitled" to conclude the Saudi-led coalition was not targeting civilians.
"He's wavered in his support for Saudi. Thousands of people are dying because of British arms sales. [Ministers] are willfully ignorant and they are trying to sustain a position where they don't have to admit that Saudi are deliberately targeting civilian infrastructure," Mr. Walton told Sputnik.
"We have got into this position where we have spent a ridiculous amount of money on a not very good plane, which is the Eurofighter Typhoon, and our entire defense strategy revolves around us flogging loads of these to Saudi because they are the only people corrupt enough to buy this tosh," Mr. Walton added.
Amnesty International said the ruling was a "deadly blow" to people in Yemen and Oxfam said there was a "clear moral case to suspend sales."