The Liberal Democrats have pledged to create three new national parks in England.
This manifesto commitment would bring the number of national parks in England up to 13, with the party proposing to spend £50 million a year maintaining them.
The Chilterns in Hertfordshire and Buckinghamshire are listed as a possible location for the new parks, in addition to the Mendips, Cotswolds and Quantocks.
Other proposed areas include the Surrey Hills, Northumberland coast and Dorset.
Liberal Democrat leader Sir Ed Davey said: “Our National Parks are some of the most beautiful parts of our country, and that’s why I’m delighted that Liberal Democrats will create three new National Parks across England.
“This Conservative party has broken too many promises to protect our countryside. Over the last few weeks, whilst travelling the country, I have heard from people about how important natural spaces are to families.
“It is hard to overstate the difference things like National Parks can make to entire communities.
“Liberal Democrats promise to create new National Parks, which could include areas like the Chilterns, as well as ensuring that our existing parks, beloved by people across the country, are protected for generations to come.”
The party has criticised the Tories for “failing” to deliver on their 2019 manifesto commitment to create one new national park.
There are currently 10 national parks in England: Broads, Dartmoor, Exmoor, Lake District, New Forest, Northumberland, North York Moors, Peak District, South Downs and Yorkshire Dales.
Planting 60 million trees a year is also a manifesto commitment for the party.
This aims to reverse the trend of declining tree planting, which has fallen from 30,000 hectares per year in the late 1980s, to just 3,000 per year in 2022/23.
The Lib Dems have also committed to banning onshore oil and gas drilling in national parks and other protected landscapes.