Six Nations chief executive John Feehan does not foresee a "genuine likelihood" of relegation being introduced in the short to medium term.
Despite growing calls for Georgia, and to a lesser extent Romania, being promoted into the competition, Feehan is happy with how things are.
"In the short to medium term there is not any genuine likelihood of that happening," he revealed to BBC Radio Wales' Jason Mohammad's show.
Feehan also launched a strong defence of Italy, who joined the top flight in 2000, saying they have been the victim of unfair criticism.
"Some comments are very unfair about Italy," he added.
"We think they have been a good addition to the Championship since they have entered.
"They have improved dramatically but other teams have improved dramatically – it's a relative thing.
"It's not that long ago they beat South Africa in the autumn series so they are capable of beating anyone on their day and worthy participants.
"We are very happy with how the Italians are approaching things.
"There is a long way to go in terms of being competitive to win the title. But on any given day they can beat any of the sides and they have done that, apart from England."