It is only five years since the then foreign secretary William Hague declared that there would be “no downgrading of human rights under this government”. Pursuing a foreign policy with a conscience was, he argued, in our “long-term enlightened national interest”.

Yet as we mark International Human Rights Day it is striking how far the Tories have strayed from this commitment, not least as their emphasis on “commercial diplomacy” has grown. Human rights concerns are now of secondary importance to trade.

Last year George Osborne’s visit to China earned praise from his host nation’s state-run media, saying he was “the first western official in recent years who has stressed more the region’s business potential instead of finding fault over the human rights issue”.

As Simon McDonald, the head of the diplomatic service, told MPs two weeks ago: “Clearly more resource is devoted … to prosperity than to human rights.” He explained that although human rights is “one of the things we follow, it is not one of our top priorities”.

That much is increasingly clear from the government’s approach to a number of international relationships, from China and Turkey to Egypt and the Gulf states. On visiting the Gulf Cooperation Council this week, the prime minister promised “a new chapter” in the UK’s ties with the region. Indeed, this was the first time a British prime minister has attended the council. Of the UK’s relationships with Bahrain and Saudi Arabia, she said: “In recent years our relationship hasn’t felt as close as it is old. I want to change that.” This is despite the desperately poor human rights records of both countries.

In Bahrain, we know that disproportionate, often lethal, force is used to suppress civilian protests, and torture is rife in prisons, and yet the UK is continuing to train the very security forces and prison services accused of these crimes.

Refugees from the conflict in Yemen, where thousands of civilians have died – the large majority as a result of Saudi airstrikes. Photograph: Ghaith Abdul-Ahad/The Guardian

In Saudi Arabia, whether it was the UK’s proposed prison training contract – cancelled only after overwhelming pressure – or the timid Foreign Office response to the mass executions carried out in the kingdom in January, the Tory government treats Riyadh’s human rights record as an inconvenient embarrassment, rather than a cause of serious concern.

Take the conflict in Yemen, where thousands of civilians have died – the large majority as a result of Saudi airstrikes. The same air campaign has crippled the country’s agricultural infrastructure, for no acceptable military purpose. And the humanitarian crisis created by the conflict is increasingly desperate, with millions now facing famine.

All this, and yet the UK government continues to arm and advise the Saudi-led coalition prosecuting this conflict, and has angrily rebuffed Labour’s calls for that support to be suspended until alleged Saudi violations of international humanitarian law have been properly and independently investigated.

If this were just evidence of a government with its head in the sand on human rights, that would be bad enough.

But Boris Johnson’s remarks in Rome, revealed by the Guardian this week, indicate something far worse. The foreign secretary is all too aware that Saudi Arabia and other countries are fighting proxy wars in the Middle East, with millions of civilians trapped in the crossfire, and yet he continues to sell Riyadh the arms to wage those wars. It is hypocrisy of the highest order.

And fresh from his latest slapping-down by Theresa May, he will spend today – International Human Rights Day – not raising these concerns openly and forcibly with our Saudi allies, but preparing to fly out to Riyadh and clarify his remarks.

Of course the government asserts that difficult discussions about human rights do take place – but behind the scenes. Does it make any difference? Not on the evidence provided.

Furthermore, while private talks are of course important, this should never be at the expense of speaking up and applying pressure when it is right and necessary to do so. By creating a perception that the UK places a higher premium on striking commercial deals than it does on promoting and protecting human rights, our reputation in the world suffers.

On visiting the Gulf Cooperation Council this week, the PM promised ‘a new chapter' in the UK’s ties with the region

With Brexit on the horizon and an isolationist president moving into the White House, we are having to redefine our place in the world and the influence we wield, more so than at any other time since the end of empire. To that end Theresa May eagerly talks up the idea of a “truly global Britain”. Yet it cannot just be one that promotes our trade and security interests; it must also promote our nation’s values – whether in respect of human rights, the rule of law, or the protection of the environment.

Prosperity need not come at the expense of this country’s proudest traditions as a beacon of justice. Reluctance to fully champion these values not only runs counter to who we are as a country, it also risks eroding our international standing just when we need it most.