Green leader Caroline Lucas has told Amber Rudd she does not know how she sleeps at night knowing the level of arms sales to Saudi Arabia.
The scathing attack was made after Ms Lucas demanded to know why the UK has now become the world’s second biggest arms dealer.
Ms Rudd claimed having a strong arms industry was necessary in order to defend the country.
The clash came as the live BBC election debate discussed terrorism and UK foreign policy.
Ms Lucas said the UK must “stop adding” to the world’s problems and singled out arms sales to Saudi, which has led a brutal bombing campaign in neighbouring Yemen.
Addressing Ms Rudd directly, she went on: “My question is this really, why is Britain the second biggest arms dealer in the world?
“Why are we selling to 22 of the 30 countries on our the Government’s own human rights watch list?
“Why do we make ten times more in arms sales to Saudi Arabia than we gave to Yemen in aid? I genuinely wonder how you sleep at night knowing those figures.”
The Prime Minister has talked a lot about boosting trade after Brexit, but campaigners have raised concerns that her desire to secure any new trade has led to a drop in ethical standards.
The Government has recently approved £3.5bn worth of arms export licenses to Saudi Arabia and a stream of British ministers have visited the kingdom to solicit trade despite its ongoing involvement in the bombing campaign in Yemen.
Ms Rudd responded: “I will make no apology for being a government that wants to defend this country.
“We will make sure that the defence budget is well funded. We make sure we will do that with a strong economy.
“We will make sure we can do that by having a strong industry.”
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