Christian groups are urging the Prime Minister to use the UK's Presidency of COP26 this year to do more to address climate change and support communities already being impacted.
The call follows the release of the latest research from the United Nations Intergovernmental Panel on Climate Change which warned of "a brief and rapidly closing window of opportunity" to avert disaster.
The grim report says that the world is already living with the consequences of climate change, with heatwaves, floods, droughts and wildfires intensifying across the globe.
The panel says that over 40 per cent of the world's population are now "highly vulnerable" to climate change and that many consequences cannot be reversed.
Responding to the report, Catholic aid agency CAFOD said it was imperative to keep "1.5 alive" as it called on governments to increase their commitments to net zero.
It is calling on rich countries to make good on their promises at COP26 and double the amount of funding for climate adaptation.
Neil Thorns, Director of Advocacy at CAFOD, said that for some communities, it was too late to adapt.
"How many crystal-clear red alerts on the climate crisis do we need before we take the urgent and meaningful action?" he said.
"Keeping warming below 1.5 degrees is the only way to avoid the huge destruction that failing those entails, especially for those living on the breadline across the world.
"We are also sadly seeing communities in East Africa and small island states where that destruction has gone beyond the ability to adapt, and they now urgently need funds to compensate for the destruction caused by a climate crisis they did not create."
He added that while some success was being seen in initiatives to restore mangroves, tropical forests and other coastal and land ecosystems, support for these projects needs to be "massively scaled up".
"Money to fight the climate crisis cannot be a bargaining chip to be played fast and loose with, this is about the survival
of all of us and the planet we love," he said.
"In the lead up to COP27, it is vital that Loss and Damage and Adaptation are top of the agenda – it's now or never for planet Earth."
Peter Kihara Kariuki, Bishop of Marsabit in Kenya, said the region was facing "severe" drought, forcing people to trek up to 17km for water and leaving many dependent on aid from the church, government or NGOs for basic necessities.
"We must raise our voices and call for ambitious action from world leaders to bring about climate justice by enacting the strongest measures to keep the global temperature rise at 1.5 degrees or below, commit to binding agreements to cut global carbon emissions, and increase support to communities like mine in Marsabit to adapt to the effects of the climate crisis," he said.
"Climate change is real for us in Marsabit. As churches, as communities, we must make sure that our voices are heard. We have a saying in Swahili: 'Kuja pamoja ni mwanzo, kukuwa pamoja ni maendeleo; kufanya kazi pamoja ni mafanikio,' which translates as 'coming together is a beginning; keeping together is progress; working together is success'."
Nushrat Chowdhury, Climate Justice Advisor at Christian Aid, is based in Bangladesh. She said the country was already on "the frontline of climate change" and that those in poverty, women and children were being impacted the most.
"This report is a wake-up call to the world that those on the front lines of this crisis need much greater support if they are going to cope with climate impacts they have not caused," she said.
She said that more funding was needed to help the vulnerable adapt and to support communities living with permanent damage.
"As COP president throughout 2022 the UK government has a vital role in leading global efforts to tackle climate change," she said.
"The main thing lacking from the outcome at COP26 was robust financial help for the world's most vulnerable, despite repeated promises from rich nations that it would be provided.
"It is now vital that the UK Government spearhead efforts to mobilise much greater funding to help the climate vulnerable adapt and to set up a fund to deal with the permanent loss and damage which cannot be adapted to.
"Only then will they have a legacy as COP26 president to be proud of."
