The south Wales neighbours are currently second and third respectively in the Championship table and appear to be firm contenders to be in the running for top-six finishes come May.
And as Speed prepares to embark on his international career in management having been unveiled on Tuesday, he knows having Wales` top two sides in one of the best leagues in the world would only benefit the national game in the country.
"It would be great, Cardiff and Swansea have very good teams this season, strong teams," he said. "If that (promotion) can happen then it`s only good for Welsh football."
Asked whether their promotion would make his job easier, Speed replied: "I hope so, they`ve both got good Academies and they produce a lot of Welsh players so if that continues and Cardiff and Swansea do get into the Premier League then it gives a better chance for those younger players to come through and play for Wales."
Meanwhile, Speed plans to hold talks in the coming days with Wales and Bluebirds captain Craig Bellamy, whom he played with under Mark Hughes and at Newcastle, regarding his international future.
Source: PA
Source: PA