Animal lovers have unleashed their anger on social media after it was reported that MPs passed a vote endorsing the idea that animals cannot feel pain or emotions.

Except it turns out that’s not quite what MPs voted for at all. Instead, they voted against an amendment to the EU Withdrawal Bill, tabled by Green MP Caroline Lucas.

The amendment would have ensured that wording of an EU treaty which explicitly describes animals as “sentient beings” was incorporated into UK law after Brexit. This would have been accomplished by repatriating a key EU protocol on animal sentience (known as Article 13 of the European Treaty) as part of our own laws.

The UK presently has no other legal instrument to explicitly recognise animal sentience, Lucas argued in the House of Commons last week, and on the New Statesman website.

But Conservative MPs, such as Robert Courts, countered that the UK’s existing Animal Welfare Act 2006 already recognises the principle of sentience. “Animals will continue to be recognised as sentient beings under domestic law,” Courts told the Commons. Lucas’s amendment also “risks creating legal confusion,” he added.

Lucas pushed back with the argument that the Animal Welfare Act 2006 does not explicitly mention sentience and applies only to domestic pets. “It does not apply to farm animals, wildlife or laboratory animals,” she said.

Yet the amendment was still voted down by 313 votes against to 295 in favour.

Is this the end of the story? Far from it. The principle of whether or not animals cannot feel pain or emotions may never have been in contention, but the response to the above debate shows that the Tories have a trust problem when it comes to Brexit.

Michael Gove’s new policies – including a ban on ivory sales, CCTV in slaughterhouses and an independent watchdog to deliver a “green Brexit” – have been welcomed by environmentalists and campaigners. But they are not enough to allay wider doubts over the government's commitment to animal welfare. (A petition on change.org is already proposing to rehome the Downing Street Cat: “We need to raise awareness and rehome Larry before it’s too late!” the petitioners write.)

Nick Palmer, head of policy at Compassion In World Farming, says that without the transference of the EU’s Article 13 covering animal sentience, there is a risk that future trade agreements could disregard animal welfare: “If Britain wanted to sign a trade agreement with the US allowing meat from especially low-welfare factory farms, under Article 13 the government would need to show that it had given full consideration to the animal welfare implications. Without this, they don’t need to bother.”

Campaigning groups such as CIWF, Avaaz and 38 Degrees are all now running petitions on the subject of animal sentience, urging MPs to vote in favour of two further possible amendments to the Withdrawal Bill (Amendment 350 and New Clause 28), which would put Article 13 into some form of law. The consideration of the bill by the House of Lords in January could also provide the opportunity for an amendment to be introduced.

Having already U-turned on an unpopular manifesto promise to hold a vote on restoring fox-hunting, the Prime Minister knows she is on shaky ground over animal rights. In today’s PMQs, she tried to kill the subject by claiming the government accepts that animals are “sentient” and that the UK will “maintain and enhance” animal protection post-Brexit.