You probably haven’t heard of Alaa Abd El-Fattah – so let me tell you about him. He’s a British citizen. He’s a father to a 10-year-old son. He’s a dearly loved brother. He’s a writer and a pro-democracy activist in Egypt, whose powerful and emotive blogging played a part in catalysing the nation’s seismic 2011 uprising. He’s also been unlawfully imprisoned by the Egyptian authorities for more than nine years – that’s a quarter of his life – and he has faced persecution and psychological torture. Now he could have just days to live. Alaa has been on hunger strike for well over 200 days. Since late May, he has been limiting himself to 100 calories a day – a teaspoon of honey and a bit of milk to keep him alive – but as of yesterday, he has returned to fully refusing food. Despite this, our government has failed to act with the consistent pressure required to secure his release. The former rime ministers Boris Johnson and Liz Truss (in her capacity as foreign secretary) deigned to “raise the case” with the Egyptian authorities. Former Africa minister Gillian Keegan has been to Cairo to visit. But since Alaa’s imprisonment nine years ago, we’ve had five different Tory-led governments – and each one has failed to secure as much as basic consular access. Alaa’s sisters, Mona and Sanaa, are camping outside the Foreign Office, desperately urging the government to step in. What is the first duty of government if not to protect the wellbeing of its citizens? This injustice has reached such a critical and urgent stage – not only because of Alaa’s rapidly declining health, but also because Cop27, taking place in the Egyptian resort of Sharm el-Sheikh, is merely days away. The world cup of climate diplomacy, Cop27 is likely to see world leaders from Joe Biden and Emmanuel Macron, to Barbados’s Mia Amor Mottley and Colombia’s Gustavo Petro, in attendance. It’s a hugely significant event for Egypt – a chance to prove itself on the global stage. Yet this conference can’t be used to paper over human rights concerns in the country. The horrific mistreatment of Alaa and other prisoners at the hands of this oppressive regime cannot go ignored, so we must use this summit, and all the diplomatic leverage we can muster, to secure a positive outcome. Cop27 can’t just be a talking shop, it must deliver climate justice for all – and standing in solidarity with Alaa and demanding his freedom epitomises this call. What is climate justice? It means acknowledging that the UK led the Industrial Revolution, fuelled by coal and colonialism. Britain, and other industrialised nations, have a particular responsibility to lead the transition to a sustainable, just and resilient world. It means recognising the obscenity of continuing with business as usual, knowing that young people, especially those in climate vulnerable countries, are paying for it with their futures. And there is no climate justice without racial justice. We’ve seen unbearable heat in India where temperatures reached a deadly 49C; and drought in the Horn of Africa, leaving millions on the brink of starvation. Yet this has received little media coverage. As youth climate activist Vanessa Nakate has said: “Africa is on the frontlines of the climate crisis but it’s not on the front pages of the world’s newspapers.” There is no climate justice without economic justice. That means a fair and equitable financial deal for the global south, with proper compensation for the harm that has been caused by rich countries burning coal, oil and gas over recent decades and centuries. Our own government has already failed to pay out more than $300m (£260m) it promised to two crucial climate funds. It must be the polluters who pay for the damage being caused. Finally, there is no climate justice without social justice. Effective climate action requires the support of civil society, the right to freedom of expression, and objective, independent reporting. Grotesque new laws like the UK’s public order bill – with banning orders, more police stop and search powers, and a host of new offences to block our fundamental human right to protest – make this all the more challenging. Climate justice, racial justice, economic justice, social justice – all are interlinked. When one is threatened, all are threatened. And this is why Alaa must be freed, and why all in the climate movement are standing in solidarity with him and his family. This matter isn’t up for negotiation: we cannot honour Egypt as Cop27 host for as long as Alaa remains behind bars. The climate movement is coming together, as one, to demand action. And we won’t keep quiet until justice is delivered. Caroline Lucas is the Green MP for Brighton Pavilion