Ministers' plans to spend more than £200 million on Cardiff Airport in the next ten years have been criticised by a rival.
Bristol Airport says it's "deeply concerned" over the Welsh Government's ten-year subsidy plan for the Rhoose airport, arguing the use of public money would give it a commercial advantage.
But bosses at the Rhoose airport say the money is necessary in order to turn around its fortunes and insist it won't have a negative impact on their Westcountry neighbours.
The Welsh Government, which has owned the airport since 2013, plans to spend a total of £205 million in an effort to safeguard jobs and boost passenger numbers, which have been slow to recover since the pandemic.
In a statement, Bristol Airport - which employs more than 4,000 people, said it already provided many jobs for people in South Wales and helped to significantly support the Welsh economy, without the need of state aid
A spokesperson added: "The CMA (Competition and Markets Authority) report highlights there's little evidence on how the Welsh Government's proposed substantial state subsidy for Cardiff Airport would minimise market distortion."
"It's suggested that incentive payments would be made to airlines, which is deeply concerning as it could affect competition between airports and airlines, leading to a negative impact on the economy and private investment in transport infrastructure."
"We have offered to work with Cardiff Airport in non-competitive areas to explore ways to reduce costs at the airport and the burden on the taxpayer, and asked for greater clarity on how the proposed subsidy will be split across airport activities, which remains unclear."
Bristol Airport, which has made a submission to the CMA, said it had previously worked with both the Welsh Government and Cardiff Airport to help support major events such as the Ryder Cup, the NATO summit, the Champions League final and the Rugby World Cup.
The CMA report found Bristol would be most affected by the subsidy plan, which the Welsh Government referred to the regulator, although other airports elsewhere in the UK had also raised their own concerns.
Following its publication earlier this month, Economy Secretary, Rebecca Evans, said: "We will take the time necessary to give full consideration to the CMA’s assessment and determine if we need to refine our proposed programme of investment on the basis of that assessment."
"I will update the Senedd in due course once we have decided on the best way forward. Until then, the Welsh Government will not be commenting further on the proposed subsidy package."
The Welsh Conservatives have also been critical of the Welsh Government's plans to use state aid for the airport.
Shadow transport minister Natasha Asghar said: "Investment in airports – as with any large-scale transport infrastructure – is crucial in order to ensure they are able to grow and thrive."
She added: “Whilst I do not dispute this positive injection of investment for Cardiff Airport, I do dispute where it is coming from."
"It remains my belief that the private sector is the right environment for this vital Welsh transport link to thrive, and that we would see much greater investment, growth and passenger take-up if the competitive free market was utilised."
“We all know that government funding is stretched. A move to the private sector would not only encourage efficiency, competition and attract greater investment and growth for Cardiff Airport, but it would free-up more taxpayer cash to spend in other areas of the budget that so desperately need help under current circumstances.”
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