Welsh language campaigners will use the National Eisteddfod Maes to launch a protest about the housing crisis in rural communities.
Homes in many areas are too costly for locals
Pressure group Cymuned announced on Monday that for the first time it would join forces with Cymdeithas yr Iaith Gymraeg (the Welsh Language Society) in a show of strength at the festival in Meifod, mid Wales.
The event - planned for Friday week - will highlight the problems faced by potential homebuyers in rural communities who cannot afford to get on the housing ladder.
The purpose of the protest is to draw attention to the housing crisis which, the two groups say, is undermining communities across Wales.
And they will be suggesting ways in which the Welsh Assembly Government could take to get to grips with the problem.
The two groups decided to organise a joint protest following the announcement by assembly Housing Minister Edwina Hart that no additional funding would be available for the Homebuy Scheme.
The scheme was set up with the aim of helping families to buy homes in their own communities.
Cymuned and Cymdeithas yr Iaith claim that, by failing to provide more finance for this scheme, the assembly has refused to take one of the simplest possible steps towards easing the housing crisis in Wales.
And they say it shows a lack of support for the future of Welsh-speaking communities.
The campaigners believe that a substantial increase is needed in the budget currently provided for the Homebuy Scheme.
They also want sufficient resources to be made available so that Housing Associations can buy houses and then let them to local families at a fair rent.
Wyn Hobson, a spokesman for Cymuned, said: "The problem of the threat to the Welsh language's existence is a multi-faceted one, and it is therefore natural that the campaign for Welsh-speaking communities today involves a number of different groups, each with its own particular emphasis and methods.
"But some matters are so central to the problem that campaigning about them is common to several groups by now.
"The crisis in the housing market is the most important of these at the present time - and it is therefore just as natural a development that Cymuned and Cymdeithas yr Iaith Gymraeg should come together to demonstrate their condemnation of the Government's inertia in this matter."
Huw Lewis from Cymdeithas yr Iaith, added that there was a need for urgent action.
"According to the Principality Building Society's latest figures, house prices across Wales have increased by almost 20% over the past year - an increase from £73,000 to £87,000 in the average price," he said.
"When we consider that wages in Wales are low - about 14% lower than the UK average - it is no surprise that local people are being priced out of the market.
"In the face of such a competitive housing market, and local people's inability to hold their own in it, one would expect a responsible government to do its best to help. "