The National Trust has announced one of the UK's biggest woodland expansion and tree planting projects as part of its plan to become carbon net zero by 2030, as the charity marks its 125th anniversary.

In a speech to mark the occasion, the National Trust’s director general Hilary McGrady announced a series of new initiatives, including 20 million new trees in ten years as part of the charity’s climate change mitigation plans.

Among the other initiatives to be announced were peat bog maintenance; renewable energy investment; "unlocking green spaces near urban areas"; and inspiring people to engage with nature.

It’s our 125th year and the National Trust has always been here for the benefit of everyone. That is why we are making these ambitious announcements in response to what is needed from our institution today.

"As Europe’s biggest conservation charity, we have a responsibility to do everything we can to fight climate change, which poses the biggest threat to the places, nature and collections we care for," McGrady commented.

"People need nature now more than ever. If they connect with it then they look after it. And working together is the only way we can reverse the decline in wildlife and the challenges we face due to climate change," she added.

It is planned that more than 18,000ha of woodland – an area equivalent to one and a half times the size of Manchester, or 42 Sherwood Forests - will be established "to lock up" 300,000t of carbon - equivalent to the electricity output of 370,000 homes a year.

The National Trust quoted research which shows that people who walk through woodland are more likely to have increased mental wellbeing and physical health, which is why the charity is looking to boost public access.

McGrady also called on Prime Minister Boris Johnson to help the charity in its endeavours with the appropriate legislation.

"The new government needs to deliver an Environment Bill with ambitious targets and a properly independent watchdog. Because we can only do so much alone. Now, more than ever, the whole environmental movement needs to pull together," she argued.