Nearly a third of arms exports authorised by Britain over the past decade were to nations identified by the government as among the worst for human rights, new figures reveal.

Military arms deals worth an estimated £39bn were approved between 2008 and 2017, £12bn of which went to states included on the Foreign and Commonwealth Office human rights “priority countries” list, according to analysis by Action on Armed Violence.

Over that period, the only country on the 30-strong watchlist to which Britain did not approve arms export deals was North Korea.

The analysis of the figures, collated by the Campaign Against the Arms Trade using export control data from the Department for International Trade, shows a clear upward trend in arms sales approved to watchlist countries, although individual years vary. The values are likely to be a “conservative estimate”, CAAT said, due to an opaque system of “open” licences that allow an unlimited number of consignments over a fixed period.

The DIT confirmed open licences are included among export licence figures, but has denied they are subject to less scrutiny.

Even if there was now to be an arms embargo for Saudi Arabia, we have funded Saudi arsenals Iain Overton, ACtion on Armed Violence

The data shows a record number of arms export licences to nations on the watchlist in 2017, almost double the previous year. While 2018 was not included in the study, the British deal to supply 48 Eurofighter Typhoons to Saudi Arabia, reported earlier this year, is worth £5bn alone, a value that dwarfs previous agreements.

In 2017, there were 855 military licence approvals for Saudi, worth £1.3bn, compared with 331, worth £680m, the previous year.

In total, 5,782 export licences for military items in countries of concern were approved last year, worth £1.5bn, up from 2,477, worth £820m, in 2016.

Some campaigners expressed concern over the doubling of licence approvals to countries with human rights abuses since the Brexit referendum in 2016.

In July, MPs from the committee on arms export control called on the government to adopt a default position of blocking arms sales to countries accused of abuses.

Saudi Arabia, Bahrain and Colombia, all countries on the FCO watchlist, were among the DTI’s “core markets” for defence and security opportunities for 2017-18.

Britain is Saudi Arabia’s second largest arms dealer after the US, providing military exports worth £10.3bn over the past decade despite continued condemnation of the kingdom’s use of British weaponry in its bombing of Yemen. UN agencies allege that the Saudi-led coalition in Yemen has violated international humanitarian standards, including widespread and systematic attacks on civilian targets.

International pressure to halt arms to Riyadh has intensified following the death of Jamal Khashoggi, the Washington Post columnist, at the Saudi consulate in Istanbul in October. Last month, Denmark and Finland joined Germany in halting future arms sales to the kingdom, although their arms exports are relatively small.

British arms exports were also approved to many countries with weapon sales restrictions imposed by the UN, the EU or both. These include China, Egypt, Iraq, Libya and Russia.

The DIT said it respects both EU and UN arms embargoes, but that it may send items not defined as weaponry to peacekeepers in such countries.

Lloyd Russell-Moyle, a member of the Commons committee on arms exports control and the Labour MP for Brighton Kemptown, said: “Approving sales of powerful surveillance equipment to regimes that hunt and kill journalists, or planes and bombs to dictators who use them on schools and hospitals, is a clear-cut violation of UK arms export control law. The government contempt for the law has inevitably resulted in UK arms exports enabling human rights abuses worldwide.”

Iain Overton, of Action on Armed Violence, said: “There needs to be more attention focused on analysis of human rights reports before we sell arms to these countries. Even if there was now to be an arms embargo for Saudi Arabia, we have funded Saudi arsenals. There is no notion of pre-planning or forewarning.”

Andrew Smith, of CAAT, called on the prime minister to put human rights ahead of arms sales. There is “little control of how these weapons will be used or who they will be used against. Right now, UK arms are playing a central role in the Saudi-led destruction of Yemen. The arms sales that are being promoted today could be used to fuel atrocities for years to come.

“The policy of arming dictatorships and pouring weapons into warzones has been pursued by governments of all political colours. It is time for Theresa May and her colleagues to end the hypocrisy and finally put human rights ahead of arms sales.”

A DIT spokesman said:“The UK operates one of the most robust export control regimes in the world. Risks around human rights abuses are a key part of our export licensing assessment, which also takes into account our obligations under the Arms Trade Treaty and other relevant rules of international law.”