Campaign groups are protesting they have been shut of the Cop26 talks on a scale never seen before – despite a pledge it would be “the most inclusive ever”.
Just four tickets were allocated to cover around 30 negotiating sessions, ActionAid said, in a huge shock to organisations which were not warned until they arrived in Glasgow.
Many of the sessions are described as “open”, but are in a section of the sprawling summit venue where non-ticket holders are barred.
“We have never been excluded like this before at previous Cop summits,” said Teresa Anderson, climate policy coordinator at ActionAid.
The summit has already been criticised as whitest and most privileged ever after visa problems, a lack Covid vaccines and changing travel rules prevented many on the frontline of the climate crisis from travelling.
Ms Anderson said civil society groups recognised that some sessions had to be closed, but called the allocation of just four tickets “outrageous”.
“Preventing civil society from watching governments and holding them accountable could have real climate consequences with communities on the front line of the climate crisis suffering the most,” she said.
“Even though this is a critical moment for the planet’s future, it’s becoming harder than ever to hold polluters’ feet to the fire.”
In May, Mr Sharma, pledged: “I have always been very clear that this should be the most inclusive Cop ever.
“I have been travelling around the world and it is very clear to me that people want to see a physical Cop, in particular developing countries want this to be face to face.”
A Cop26 spokesperson said: “We are working tirelessly to ensure an inclusive, accessible and safe summit in Glasgow.
“As we seek to ensure a Covid-safe Cop, the capacity of rooms has been reduced to enable social distancing.”
Campaigners say activists have been thwarted in their attempts to reach Cop26 by a “hostile attitude” from the Home Office towards those travelling from developing countries, with many visa applications refused.
There has also been a failure to honour a pledge to offer Covid vaccines to all delegates, leaving many to search for jabs in countries with few of them.
Until this month, travel was effectively banned from countries on the UK’s red list – and there has been an accommodation crisis in Glasgow, despite attempts to link up travellers with people with spare rooms.