Reduced bus services could increase loneliness and isolation amongst older people, according to Age Cymru.
It is calling on the Welsh Government, local authorities, and bus operators to work together to "develop sustainable services for community across Wales".
The charity's warning that bus services "provide a lifeline to thousands of older people and if they are drastically cut, many could find themselves plunged into a life of isolation and loneliness".
It comes amid reports from the Confederation of Public Transport that Wales could lose up to a quarter of its services.
"The bus service provides a crucial lifeline for many"
Many elderly people use buses to attend hospital appointments or visiting their GP, according to the charity.
It adds that many catch a bus to buy food, access cash, pay their bills, socialise with family and friends, attend day centres, lunch clubs, and places of worship.
The charity also thinks that owning a car is not an option for many older people and taxis can be "prohibitively expensive, so together with community transport, the bus service provides a crucial lifeline for many".
Victoria Lloyd, Age Cymru's Chief Executive said the "impact of poor public transport on the lives of older people can be profound".
A Welsh Government spokesperson said: "We provided the bus industry with vital support through the pandemic and announced a further £46m in May to support operators and protect the Traws Cymru network.
"Our priority up until now been ensuring services continue to run and that we are not facing wholesale collapse of the industry. We are now working on the funding offer for next year.
"We are supporting local authorities across Wales with bus-priority measures to keep passengers moving and make bus travel more attractive."
Commenting on the news that loneliness and isolation could increase among older people if bus services are reduced, Welsh Conservative Shadow Transport Minister, Natasha Asghar MS said:
“Isolation and loneliness is a heartbreaking concern already among older people, for this to increase due to Labour’s cuts to bus services is very concerning.
“Labour need to address these concerns immediately and reevaluate their priorities, otherwise they will leave a generation of vulnerable people at risk.”
Also commenting, Welsh Conservative Older People’s Champion and Shadow Minister for Equalities, Altaf Hussain MS added:
“It is important that the Labour Government get this right, we cannot abandon the older generation who rely on the bus service.
“Many of our older population suffer from health-related issues that will only be exacerbated by the stress of bus cuts, leaving them isolated and alone.
“Labour ministers must take more care of our elderly population, they have already let them down with inhuman NHS waiting lists, they cannot also leave them isolated with bus cuts.”
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