Human rights group Reprieve has accused the Foreign Office of being complicit in abuses in Bahrain and failing to be transparent about its £5m security and justice reform programme in the kingdom.

Between 2012 and 2017, funding for the programme was largely drawn from the controversial conflict, security and stability fund, a cross-government reserve that supports global security and peace building in conflict zones, according to freedom of information requests.

The fund has a budget of £1.2bn a year, split between overseas development assistance, which counts towards Britain’s 0.7% aid target, and other funding. It was set up under the auspices of key government departments, including the Department for International Development and the Foreign Office, and its priorities are dictated by the national security council.

The CSSF was recently criticised by the UK aid watchdog for serious shortcomings in the way it operates. It was found to have been insufficiently rigorous in applying safeguards to prevent collaboration with foreign entities with suspect human rights records.

In its report, Reprieve said that despite the training of prison officers, police and other officials by British companies in the kingdom since the Arab spring, the number of inmates on death row has tripled, torture in detention has continued, and executions have resumed for the first time since 2010.

Three men, Sami Mushaima, 42, Ali al-Singace, 21, and Abbas al-Sameea, 27, were executed in January last year, despite alleging torture and forced confessions, according to Human Rights Watch.

Reprieve, said that, by providing training to groups that later backed the executions of dissidents – and because of its failure adequately to investigate torture allegations – the British government was complicit in human rights abuses in Bahrain. The report was co-authored by Bahrain Institute for Rights and Democracy.

The report comes after an aid watchdog criticised the conflict, security and stability fund (CSSF) recently for serious shortcomings in the way it operates, including that it had been insufficiently rigorous in applying safeguards to prevent collaboration with foreign entities with suspect human rights records.

Maya Foa, director of Reprieve, called on Britain to require Bahrain to take basic anti-torture steps as a condition of further assistance, and to be more transparent about funding.

She said: “A global Britain should be proudly promoting human rights and the rule of law, not undermining them in secret.

“The only way for the British public to be confident their money is not leading to abuses abroad is for the government to publish a full and transparent account of projects we are funding and the human rights assessments for each.”

Between 2016 and 2017, the FCO spent £1.5m on British expertise to reform Bahrain’s security and justice system, through the CSSF.

However, this year, the UK’s contribution to the project will come from two new sources, the Global Britain Fund and the Integrated Activity Fund, which Reprieve say is more opaque.

A Foreign Office spokesperson said: “We regularly raise concerns on specific issues at a senior level with the government of Bahrain, but it is not good enough just to criticise countries from the sidelines. Only by working with Bahrain can we bring about the changes we would like to see in the country.”

The spokesman welcomed a recent decision by Hamad bin Isa al-Khalifa, the king of Bahrain, to commute four death sentences.