Six Nations set for 'relegation'
"We need to change the format of the Six Nations Championship," Lapasset told French newspaper Le Figaro.
"If we want to look to the future, then the competition needs to be more open with a promotion-relegation system.
"It could be either direct, or after a play-off. But you need to quickly give a vision and some hope for these teams," he added, talking about second-tier European countries such as Georgia, Romania and Russia.
The debate for relegation and promotion emerged after Georgia's strong showing at the 2015 World Cup, and intensified after Italy's woeful displays in this year's Six Nations.
Italy were the last side added to the tournament in 2000, 90 years after France became the first country from outside the British Isles to take part.
President of rugby's world governing body since 2007, Lapasset will leave the job in May, with Englishman Bill Beaumont the only declared candidate to succeed him.
"The only problem will be the Six Nations. It will be difficult for him to open it up, but it has to expand," said Lapasset.
"There will be a Latin vice-president in Argentine Agustin Pichot. That opens prospects. That partnership has a good balance that can help bring rugby a little further."
Agence France-Presse
