The Government licensed the sale of £160,000 worth of bullets and body armour to the Yemeni government after Prince Andrew met the country's Prime Minister for trade talks.
It was the Duke of York's third meeting in quick succession with leaders of the small Arab republic, which has been ruled with an iron hand for more than 20 years by President Ali Abdullah Saleh, but is now experiencing the wave of popular protest sweeping the Middle East.
Though less well-publicised than the more violent events in Libya, the Yemeni protests have persisted for weeks.
Yesterday, a man died from gunshot wounds after troops fired on hundreds of protesters who had gathered in the university campus in the capital, Sana'a. Five others were seriously injured and about 90 more received minor injuries after troops used live ammunition, rubber bullets and tear gas.
Prince Andrew held three meetings with Yemeni leaders between September 2009 and January 2010, all on the pretext of boosting British exports. The records of the Export Control Organisation, the body which regulates arms sales overseas, show that during the first quarter of 2010 – just after the prince's third meeting – licences were granted for the sale of £160,245 worth of bullets and body armour to the Yemenis.
Prince Andrew's role as UK trade envoy has been called into question because of his friendship with the American hedge fund manager Jeffrey Epstein, after the billionaire convicted paedophile had been released from prison and placed on the US sex offenders' register.
The prince, who has admitted that this friendship was "unwise", was reported yesterday to have received "100 per cent" backing from the Queen. He has also, in public at least, been given the backing of Downing Street, despite private hints from senior figures that it would cause no distress in Westminster if he were to resign.
Further criticism is likely after it emerged that, as recently as Monday this week, he has been lobbying an MP to help boost trade with Azerbaijan, a nation accused of torturing protestors.
His dealings with Yemen's leaders have all been in his capacity as UK Trade Representative and carried the blessing of the UK and US governments, which see President Saleh as an ally in the war against al-Qa'ida.
President Saleh has ruled Yemen since the two halves of the country merged in 1990. Yemen ranks 146th out of 178 in the "corruption index" issued by the pressure group Transparency International.
Prince Andrew met President Saleh in September 2009, when both were visiting Jeddah, in Saudi Arabia, where he told the President that the UK wanted to get more involved in Yemen and that it wanted to increase investment in the country.
Two months later, the prince was a guest at the presidential palace in Sana'a, where he met President Saleh and other leaders, including the Prime Minister Ali Mohammed Mujawar and was guest of honour at a lunch hosted by the President. According to the Yemeni account of the visit, the prince praised the country's "unity, stability and development" and urged them to open up to more British investment.
Yemeni sources say Prince Andrew met Ali Mujawar in London in January on the fringe of a conference hosted by David Miliband to discuss the terrorist threat in Yemen, though it was not on the official list of the prince's engagements. Despite the growing evidence of instability, the prince again stressed "the British willingness to advance its cooperation with Yemen, particularly in commercial and investment areas."
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