ANGUS Robertson has called on Theresa May to adopt an “ethical foreign policy" and follow Americas’s lead by cutting arms sales to Saudi Arabia.

The SNP leader at Westminster said that Britain had sold £3.3 billion of arms to Saudi Arabia since its bombing campaign began in Yemen; some of them were made in Scotland.

During Prime Minister’s Questions, he told Mrs May: "The US Government has just said, and I quote, ‘systematic endemic problems in Saudi Arabia's targeting drove the US decision to halt a future weapon sale involving precision guided munitions’.

"The Saudis have UK-supplied precision guided Paveway IV missiles; they're made in Scotland. The UK has licensed £3.3bn worth of arms to Saudi Arabia since the beginning of the bombing campaign. What will it take for the UK to adopt an ethical foreign policy when it comes to Yemen?"

The PM stressed that the intervention in Yemen was UN-backed. "As I have said previously, where there are allegations of breaches of international humanitarian law, then we require those to be properly investigated.

"We do have a relationship with Saudi Arabia; the security of the Gulf is important to us.

"I would simply also remind him that actually, Saudi intelligence, the counter-terrorism links we have with Saudi Arabia, the intelligence we get from Saudi Arabia, has saved potentially hundreds of lives here in the UK," she noted.

Earlier, Mrs May had pointed out how Britain had a very strict regime of export licences, explaining: “We exercise that very carefully and in recent years we have indeed refused export licences in relation to arms, including to Yemen and Saudi Arabia.”

After PMQs, Mr Robertson claimed the decision by Washington to halt arm sales was a “huge embarrassment” for the UK, which was now lagging behind.

"The SNP has long campaigned for the UK Government to halt arms sales to Saudia Arabia; the issue has been raised 60 times by SNP MPs…across 25 debates.

"The atrocities in Yemen are of devastating proportions and it begs the question of what needs to happen for the UK Government to finally take a stand and stop selling arms to a country accused of killing civilians," he added.

Elsewhere, Kate Allen, the director of Amnesty International UK, said: "It's really shocking that Theresa May is still burying her head in the sand over the UK's responsibility to suspend arms sales to Saudi Arabia, given the clear risk that UK weapons could be used to commit breaches of international humanitarian law in Yemen.”

Thousands of Yemeni civilians had already been killed and injured by the Saudi-led coalition's reckless and indiscriminate bombing of homes, hospitals, schools and factories.

"Earlier this year, we revealed how the Saudi coalition had been using British-made cluster bombs in their attacks near Yemeni villages and farms in the north of the country.

"With the USA now suspending exports of precision-guided weapons to Saudi Arabia, the UK is being exposed as an utterly hardline, conscience-free arms exporter.

"We've said it before but we need to keep saying this - the UK should immediately suspend all further weapons sales to Saudi Arabia that risk fuelling further atrocities in Yemen, before it brings further disgrace upon itself over its part in this brutal war," she added.

Prime Minister Abdulaziz bin Habto, who leads the rebel Houthi government in Yemen, has accused the UK of war crimes after reported discoveries of British-made weapons in bombed parts of the country.

The Foreign Office said it was aware of reports of an alleged airstrike on a school using UK-supplied weapons and was seeking further information.

"The UK Government takes all allegations of international humanitarian law violations very seriously. We will analyse this allegation in the usual way,” said a spokesman.

Saudi Arabia has denied causing large-scale civilian deaths, saying it is making every effort to avoid hitting civilian targets.

Thousands of people have been killed in the civil war with nearly three million displaced since it began in 2014.