That includes "early years" provision such as children's centres, which have already been squeezed.
It added: "We are dramatically extending high quality early years provision.
What does good early years provision look like, and how can it best be funded?
As is the government's focus on early intervention, high-quality early years provision and stable family environments.
"We urge local politicians to protect early years provision, which can have a life-long, positive impact on young children and their families," says the letter.
While Broomhall's children's centre and post-three nursery will remain, local people have started a campaign to save the early years provision.
Here, too, widespread public support will be crucial to the successful implementation of the government's vision for early years provision to meet the needs of the modern labour market and our youngest children.
The plea, coordinated by the expert organisation Early Education, acknowledged that government spending cuts meant difficult choices, but argued that cutting high-quality early years provision was a false economy.
George Osborne told BBC1's Andrew Marr Show: "We have got to make some tough decisions, but the priority is healthcare, children's education, early years provision and the big infrastructure developments like Crossrail, Mersey Gateway, the synchrotron, broadband.
Along with a growing pressure on resources, we face skill shortages especially of social workers; intense pressure to find additional places for children in high-quality early years provision, and a looming lack of schools places.
