The Cotswolds and the Gower Peninsula in Wales could be at risk if the government does not produce a world-leading policy for food and faming post-Brexit, the CLA has said.
Forty six Areas of Outstanding Natural Beauty (AONB) across England and Wales are being celebrated during ‘Outstanding Week’ (17-25 September) to highlight their national importance.
The week is to ensure their character and qualities are protected for all to enjoy.
But the CLA, which represents landowners, farmers and rural businesses, says any uncertainty over the future funding for food, farming and the environment after 2020 could lead to these areas at risk of becoming "economically and environmentally unviable."
CLA President Ross Murray said: "It is right to celebrate these naturally breathtaking rural areas.
"We are always keen to welcome more visitors into the countryside, but it should not be forgotten that AONB are living, working landscapes.
"It is critical that the right government policies and funds are designed which will enable farmers and land managers to sustain these distinctive landscapes for future generations.
"Brexit has created a period of uncertainty. Although we are assured the current support for agriculture and rural development will continue at the same level until the end of 2020, after that is unknown.
"The government has a duty to ensure food, farming and the environment are not let down by a lack of funding challenge because communities, businesses, landscapes and wildlife are all dependent on the viability of the rural economy."