Noel Mooney left Uefa to become FAW chief executive in August, 2021
Chief executive Noel Mooney says the Football Association (FAW) is backing those who are opposed to Fifa's plans for the World Cup to be played every two years.
Uefa, of which the FAW is a member, is among the bodies who have rejected the idea.
Mooney says the impact on women's football must also be considered.
"We are against the propositions very firmly," said Mooney.
Former Arsenal manager Arsene Wenger is leading a group looking at the men's game, while ex-United States coach Jill Ellis is overseeing an advisory group working on proposals for the women's game.
Fifa's plans may also result in a clash between World Cups and the Olympic Games - a significant event in the women's calendar.
Uefa and 10 of Europe's women's leagues joined men's leagues in voicing their opposition to the world governing body's idea, which would mean the women's World Cup taking place in the same summer as a major men's tournament.
Mooney told BBC Radio Wales Sport: "We had a call recently with Fifa and the 55 presidents and CEOs of the European national associations, and our position is pretty clear at this stage that we are not with a World Cup every two years.
"The Euros, as we know here in Wales, is quite a spectacular thing. There's other issues around women's football they're trying to do that we're not particularly mad about.
"You've got September, October, and November with these nice spikes of international matches.
"This proposal would actually bring them all into October - eight matches all in October, I don't know how that would work.
"I don't think it's good for international football, so we are against the propositions very firmly."
Mooney also says the effect on players cannot be ignored.
"There's more and more demands being made of [players] - they need a summer break, they need time for their bodies to recover, they need time with their family and we shouldn't forget that.
"I think in this World Cup every two years, if you then had a Euros in the years outside, they'd be playing in a major tournament every year.
"Where would the Olympics fit? We shouldn't try to muscle that out of the way, we need to support our friends in other sports, to let them have their time as well.
"If you had a major tournament every year, would that overshadow the women's major tournaments?
"At the moment there's space for them to exist. You've got the [women's] Euros coming up in England, and they will get a lot of coverage when that comes up.
"If you went against that, would you be overshadowing the women's Euros or Women's World Cup?
"At the moment, Uefa is very much against this two-year World Cup.
"I don't see that changing, and it'll be up to Fifa to come up with a better idea and a better proposal for world football."
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Mooney also welcomed United Kingdom chancellor Rishi Sunak pledging a further £11m for the UK and Republic of Ireland's bid to host the 2030 World Cup.
Despite England receiving a one-match stadium ban following unrest at Wembley during the Euro 2020 final, the government has insisted that the bid is "very strong".
Mooney said the financial backing "wasn't unexpected".
He added: "We are quietly confident that we've got a really strong proposition to bring to the world as to why they should hold a World Cup on these islands.
"We're quietly confident that we're going in the right direction - we'd have to put forward a bid relatively soon.
"I think it's the right thing to do. I think hosting 10 World Cup matches in Cardiff in 2030, with the top nations in the world playing football here … if Wales, to the world, was seen as a great host, which I'm sure it would be, I'm sure it would be a really positive thing to do."
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Source: bbc.com