Hundreds of activists at the COP27 climate summit in Egypt’s Sharm el-Sheikh have marched calling on industrialised nations to pay for the impact of global warming and demanding freedom for political prisoners.

Chants of “free them all” and “no climate justice without human rights” rang out as activists marched on Saturday through the conference’s “Blue Zone”, which is considered UN territory and ruled by international law.

“Pay for loss and damage now,” Friday Nbani, a Nigerian environmental activist leading a group of African activists, said on Saturday.

Many demonstrators, alongside several vulnerable countries, have called for “loss and damage” payments, or financing to help pay for climate-related harms, to be central to negotiations. “Africa is crying, and its people are dying,” Nbani said.

Hindou Oumarou Ibrahim, an environmental and Indigenous rights activist from Chad who is also a UN climate “champion”, said her people were dying because of floods and droughts, while Indigenous people in the Pacific were losing their homelands.

“We cannot accept any decision here without loss and damage reparations,” she told the crowd, adding that keeping to the 1.5C global warming limit in the Paris Agreement “is not negotiable”.

While the Egyptian COP27 presidency mandated that demonstrations must be approved by organising authorities and should take place only in a particular zone, activists said they got UN permission for their activities outside the designated area.

Sanaa Seif, the sister of jailed Egyptian-British dissident Alaa Abd el-Fattah, marched in the front line under a banner reading, “You have not yet been defeated” – the title of Abd el-Fattah’s book, which has become a rallying cry for summit activists.

In 2015, he was sentenced to five years in prison after being found guilty of violating protest laws two years earlier, when the current President Abdel Fattah el-Sisi led a coup against the late President Hosni Mubarak’s democratically elected successor, Mohamed Morsi. Abd el-Fattah began consuming “only 100 calories a day” in April, his family said, to protest the conditions he and about 60,000 other political prisoners faced in the country.

Since November 6, when the climate summit kicked off, he has stopped all water intake. The family made an official request for a presidential pardon from President Sisi on Friday, Abd el-Fattah’s other sister Mona Seif announced.

US national security adviser Jake Sullivan said on Saturday his government was doing “everything it can” to secure Abd el-Fattah’s release.

President Joe Biden, who flew in on Friday, had “an extended discussion on the issue of human rights” with President Sisi, Sullivan said, and directed his officials to work with the Egyptians on several cases, including Abd el-Fattah’s.

Demonstrators also called for drastic reductions in greenhouse gas emissions.

Emissions continue to rise, but scientists say the amount of heat-trapping gases needs to be almost halved by 2030 to meet the temperature-limiting goals of the Paris climate accord.

Activists chanted “keep it in the ground” in reference to their rejection of the continued extraction of fossil fuels.

On Friday, some of them heckled US President Joe Biden’s speech and raised an orange banner that read, “People vs. Fuels” before being removed. One of the activists, Jacob Johns, had his access to the conference revoked as a result.

The demonstration came at the end of the first week of the two-week summit, when typically protest action at climate summits is at its height.

COP27 featured a light agenda for Saturday, and a full day of rest on Sunday before the focus shifts to discussions around a final document meant to reflect what has been agreed upon and achieved at the summit this year.

Talks are expected to intensify through next week until the conference concludes on November 18, as delegates jockey for their priorities to be included in the closing declaration.

Rallies also called for an end to a crackdown on environmental activists and minorities and for the rights of Indigenous groups, women, labourers and people with disabilities, especially in developing nations.

Protest organiser Asad Rehman read a statement from Abd el-Fattah’s sister, as Seif stood silently next to him.

“I came here thinking I would be alone,” read the statement. “I am sure that those in power thought that my voice would be drowned out and ignored. Instead, I found that my family was already here waiting for me.”