The release of Alaa Abd el-Fattah, the detained British-Egyptian pro-democracy activist who is on hunger strike, has become the defining issue for British-Egyptian relations, the former British ambassador to Egypt John Casson has warned. His comments came as Abd el-Fattah’s aunt, the novelist Ahdaf Soueif, said there was a danger the British “are allowing themselves to be fobbed off with the excuses they have been given since last December when we started asking for consular visits”. The UK prime minister, Rishi Sunak, met Egypt’s president, Abdel Fatah al-Sisi, on Monday night on the margins of the Cop27 conference and said afterwards he had raised Abd el-Fattah’s plight, but nothing substantive has yet emerged on his potential release. Abd el-Fattah, a pivotal figure in the Arab spring, has been on hunger strike and is refusing to take water. Casson, who was UK ambassador to Egypt from 2014 to 2018, said “the next 24 to 48 hours are crucial”, and that now Sunak has had his meeting “it is really important today that across the British government the system is mobilising to make sure the Egyptian government realise that we mean it”. He added: “It is important that intelligence and military channels in the UK tell their opposite numbers in Egypt what is at stake. The way Egypt works is they realise an issue has got to the vital heart of the relationship if it is communicated by military and intelligence. Then they realise it is the defining issue for our relationship now.” Abd el-Fattah’s life was in danger, Casson said. “This is not just one of those cruel things that happens, it is created by choices that people in Egypt are making. It is a fundamental government duty to protect our citizens and I really do not know what else we think we would be protecting by holding back at this stage. This is the time for maximum pressure.” He questioned whether Sunak should have met Sisi before receiving assurances over the British embassy getting its basic rights on consular access. “The one thing Egypt craves is to be embraced as a normal country again after all the crackdowns in the Arab spring. If we keep giving them what they want for nothing, they will sit back and ask for more.” He said the Foreign Office should focus on what gets results. “It needs to set out very clearly the long-term consequences for military exchanges, intelligence relationships, trade and investment so Egypt does not have a sense it is not being normalised and politically embraced.” Casson said that the UK government should examine whether it should continue to provide the access it does to Egyptian officials given the fact that Egypt is blocking consular access to a British citizen. He described Abd el-Fattah as a man of vision and values for the future of Egypt, but the Egyptian government seems to fear him and persecute him. He said the case raised questions of whether the UK “needed a more hard-headed look after Brexit at where we are with our diplomacy and to better understand the power we have now and how we use it. For the last seven years in many ways we have not had a foreign policy in the way we used to mean it, in terms of a view of the world we want to live in, backed up by a real notion of our power, and our leverage and the cards we have to play.” He added: “It is hard to name issues in which Britain has made the running in the world,” saying that “this was partly because British diplomats had been quite traumatised by Brexit, and became very timid”. He said “a succession of prime ministers and foreign ministers had rather been distracted by domestic political signalling and so there had been no sustained focus on getting the outcomes we need”.