An environmental charity says it will stop working with Sheffield Council while the authority carries on felling trees.
Trees for Cities, which works to create greener urban areas, said it was 'deeply concerned' about the trees being cut down under the council's Streets Ahead programme.
In a statement on its website the charity called for the council to 'immediately suspend' felling work until a way forward was agreed 'amongst all key stakeholders'.
Trees for Cities has most recently worked with the authority on a project to create 'urban woodlands' by planting 7,500 trees, but has been involved in the city for a decade.
The statement said: "Trees for Cities has planted trees in Sheffield over the past 10 years undertaking projects in schools and creating urban woodlands and community orchards.
"Over this period we have planted over 25,000 trees.
"To deliver these projects, we have worked closely with the community forestry team of Sheffield Council’s Parks Countryside Service and we have always received great support.
"It is with deep regret, however, that whilst these practices continue, Trees for Cities is unable to develop further projects on council land.
"For the sake of the city’s trees, inhabitants and wildlife, we implore the decision-makers in the city council, Amey and local politicians to urgently seek an acceptable resolution to this situation."
The charity said it accepted that in all urban areas there would be a 'small percentage' of dead, dying, diseased or dangerous trees that need to be removed. But it claimed a number of healthy mature trees have been felled in Sheffield 'where other options were available'.
The statement added: "At the very ethos of Trees for Cities is a belief that no healthy street tree should be destroyed before the end of its natural life, apart for in exceptional circumstances.
"Street trees have an irreplaceable aesthetic value that help make our cities liveable.
"They provide essential ecosystem services such as cleaning and cooling of the air, absorption of greenhouse gases and the reduction of flood risk. They are associated with a number of social health benefits.
"They create a connection with nature and the seasons. They act as a habitat for wildlife and protected species.
"It can take up to 100 years for a tree to reach maturity and provide its full social and environmental benefits, and hence the removal of any tree should be deemed as a last resort and alternatives such as engineering solutions should always be adopted where possible.
"It is absolutely unacceptable for any tree to be removed for economic gain."
The council has repeatedly defended its actions, saying every felled tree would be replaced and new ones planted to eventually increase the overall number in the city.
About 10,000 trees are due to be replaced under the Streets Ahead programme.
On Friday Coun Bryan Lodge said delays caused by protests and court cases would cost the Sheffield taxpayer 'millions'.
He added: "The vast majority of the people of Sheffield are now starting to say 'this is costing money - get on with it'."