Tim Farron is calling for the law to be changed to require ministers to approve personally each sale to countries with poor human rights records, such as China, Russia, Pakistan and Saudi Arabia.
He is also backing fresh controls to stop British weapons falling into the hands of repressive regimes via a third country, and for greater transparency in the system governing arms sales. British-made Tornado and UK-supplied Typhoon jets are reported to have been among the 100 Saudi warplanes used recently to strike camps used by rebel forces fighting the Yemeni government.
The Independent has also disclosed that Britain approved the sale of arms to Israel worth £7m in the six months before its offensive on Gaza last summer, including components for drones, combat aircraft and helicopters, along with spare parts for sniper rifles.
Policy on arms sales, which is split between the Foreign Office and the Department for Business, Innovation and Skills, is expected to be reviewed by the Government this year, although Whitehall sources played down the prospect of major changes.
Mr Farron acknowledged strict rules were already in place over weapons exports, but said the system was “still dangerously weighted in favour of arms sales to countries which our own Foreign Office has serious concerns over”.
He said: “We have to stop a situation where one half of the Government spends excruciatingly tragic hours documenting the horrific murder and oppression of citizens in countries across the world and the other half gives the green light to arms exports to that country.
“This isn’t about being anti-business or afraid of trade. We simply cannot stand with our heads held high on the international stage when we are selling arms to countries with serious human rights abuses.” Tim Farron, the Lib Dem leadership frontrunner, is calling for an arms policy overhaul
Under the current system, the Foreign Office recommends approval of an export licence unless it judges there is a “clear risk” the exports might be used for internal repression or other human rights abuses.
Mr Farron wants this replaced by a “presumption of denial” of exports to the 27 states which the Foreign Office lists as “countries of concern” in its annual human rights report, with exceptions only made when they were approved by ministers.
The former Lib Dem president would also require “end-user certificates” which would certify that the buyer of arms would not sell them on to another country, with the Government required to report to Parliament annually on the certificates.
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UK’s £12.3bn arms sales to repressive states
Andrew Smith, spokesman for the Campaign Against the Arms Trade, said: “We would welcome any steps which stop weapons getting to repressive dictatorships and being sold into war zones.”
He claimed there had been a “lack of political will” to tackle the issue under previous governments. Britain is currently exporting to more than 20 of the states on the Foreign Office list.
Burma, North Korea, Somalia, Syria, Turkmenistan and Zimbabwe are among the recipients of UK-made weaponry.
Supporters of tougher arms export controls include Amnesty International, Oxfam and Saferworld.
Fallon defends record: Nato spend to be met
Michael Fallon has insisted Britain should “fulfil our commitments” amid questions over whether the Government will abandon the 2 per cent Nato target for military spending.
The Defence Secretary refused to commit explicitly to maintaining the outlay as a proportion of GDP. But he dismissed criticism that the UK was withdrawing from the international stage.
Speaking on the BBC’s ‘Andrew Marr Show’, Mr Fallon said figures due out this week would confirm the 2 per cent threshold is being met.
Pushed on whether spending would remain at that level, he replied: “I want us to fulfil our commitments.
He added that the EU must go beyond dealing with the “symptoms” of the migrant crisis and tackle its roots in Africa.
Mr Fallon said the UK’s international aid budget was being used to help “stabilise” countries, but warned a much more “comprehensive” approach was needed.
“At the moment we are simply dealing with the symptoms of the problem, helping to rescue people in the Mediterranean,” he said.